Difference between revisions of "CUPS (简体中文)"
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(Postscript Printer Description)。 另外，''foomatic-filters'', ''gimp-print'' and ''hplip'' 已经自带了很多 PPD 文件，CUPS会自动检测他们.
Revision as of 05:13, 5 January 2012
来自 CUPS' site:
- "CUPS 是苹果公司为Mac OS® X 和其他类 UNIX 的操作系统开发的基于标准的、开源的打印系统".
- 1 介绍
- 2 安装 CUPS
- 3 配置
- 4 共享打印机
- 5 Appendix
- 5.1 Alternative CUPS Interfaces
- 5.2 PDF Virtual Printer
- 5.3 Online Resources
- 5.4 Specialized Cases
- 5.5 Another Source for Printer Drivers
- 6 Troubleshooting
CUPS网站的介绍: "The Common UNIX Printing System ("CUPS")CUPS 是个跨UNIX平台的打印解决方案. 它基于“网络打印协议”并且为大多数Postscript和光栅打印机提供完整的打印服务。CUPS基于GUN GPL协议提供。”虽然有其他的打印程序包例如LPRNG，但CUPS是相当流行和相对容易使用的。它是Arch linux及许多其他Linux发行版缺省的打印系统。 It is based on the "Internet Printing Protocol" and provides complete printing services to most Postscript and raster printers. CUPS is provided under the GNU GPL..." Although there are other printing packages such as LPRNG, CUPS is quite popular and relatively easy to use. It is the default printing system on Arch Linux as well as many other Linux distributions.
Troubleshooting CUPS & components CUPS及组件的疑难解答
在‘/etc/cups/cupsd.conf’文件中设置‘LogLevel’是让打印机工作最好的方法：The best way to get printing working is to set 'LogLevel' in '/etc/cups/cupsd.conf' to:
然后像这样查看'/var/log/cups/error_log'文件的输出：And then viewing the output from '/var/log/cups/error_log' like this:
tail -n 100 -f /var/log/cups/error_log
在输出中左边的字符排列如下：The characters at the left of the output stands for:
D = Debug E = Error I = Information 等等...
这些文件也可能被证明是有用的。These files may also prove useful.
/var/log/cups/page_log '每次打印成功后增加的词条spits out a new entry each time a print is successful.' /var/log/cups/access_log '所有活跃的cupsd http1.1服务器列表lists all cupsd http1.1 server activity'
当然，如果想解决你的问题，重要的是知道CUPS怎样工作，这多多少少是正确的：Of course it's important to know how CUPS work if you want to solve your problems, this is somewhat correct:
- 当你选择‘打印’时，应用程序会发送一个.ps文件（PostScript，是主要用于电子产业和桌面出版领域的一种页面描述语言。）给CUPS（99%的程序会这样做）。An application sends a .ps file(PostScript, a script language that details how the page will look) to CUPS when you select 'print'(99% of apps do).
- CUPS然后读取你打印机的PPD文件（打印机描述文件）并且计算出它需要哪种解释器去将.ps文件转换成一种打印机认识的语言（像PJL，PCL）。通常它需要ghostscript。CUPS then looks at your printers PPD file(printer description file) and figures out what filters it needs to use to convert the .ps file to a language that the printer understands(like PJL,PCL). Usually it needs ghostscript.
- GhostScript取得输入并且计算出它需要哪个过滤器，然后将它们转变成打印机能读懂的.ps格式。GhostScript takes the input and figures out which filters it should use,then applies them and converts the .ps file to a format understood by the printer.
- 然后它被发送到后端。举个例子，如果你有打印机连接到USB端口，它就用USB后端。 Then it is sent to the backend. For example, if you have your printer connected to a USB port, it uses the USB backend.
打印一个文档并且查看'error_log'文件来得到关于打印队列更多的细节和正确地印象。Print a document and watch 'error_log' to get a more detailed and correct image of the printing process.
# pacman -S cups ghostscript gsfonts
如果正常的cups不起作用，你可以试试从 AUR 安装 AUR 。（建议三星的USB打印机试用）
- cups - 就是传说中的CUPS软件
- ghostscript - Postscript语言的解释器
- gsfonts - Ghostscript标准Type1字体
- hpoj - 如果你使用 HP Officejet, 你应该再安装这个包，遵循指导避免发生错误. 更多信息见 thread at launchpad/hplip.
如果你的系统要通过 Samba 使用网络打印机，或者这台机器要作为打印服务器向其它windows客户端提供服务，你还需要安装Samba:
# pacman -S samba
- gutenprint - 一组质量非常好的驱动集合，支持的目标机型包括 Canon, Epson, Lexmark, Sony, Olympus；以及配合CUPS/GhostSscript/Foomatic/GIMP使用的 PCL printers。
- foomatic-db, foomatic-db-engine, foomatic-db-nonfree, and foomatic-filters - Foomatic 是一个基于数据库的，集成自由软件打印机驱动和脱机打印程序的系统。安装 foomatic-filters 可以解决 cups error_log 报告错误 "stopped with status 22!".
- hplip - HP GNU/Linux 驱动. 支持 DeskJet, OfficeJet, Photosmart, Business Inkjet 和一些 LaserJet printer 型的, 以及一些兄弟打印机。
- splix - 三星驱动，支持SPL打印机(SPL：Samsung Printer Language) (USB打印机要配合使用 AUR 的 AUR )
- ufr2 - 佳能 UFR2 驱动，支持LBP, iR 和 MF 系列打印机. 在 AUR 能找到这个包。
- cups-pdf - PDF虚拟打印机，这个东西可以把发送给他的打印任务输出为PDF文件。
取决于你的打印机，不一定需要进行这个步骤，如果没什么问题可以直接跳到下一节进行配置了。因为标准的CUPS安装已经携带了很多PPD(Postscript Printer Description)。 另外，foomatic-filters, gimp-print and hplip 已经自带了很多 PPD 文件，CUPS会自动检测他们.
这是一句来自 "Linux 打印网站" 的内容解释什么是 PPD 文件:
- "For every PostScript printer the manufacturers provide a PPD file which contains all printer-specific information about the particular printer model: Basic printer capabilities as whether the printer is a color printer, fonts, PostScript level, etc., and especially the user-adjustable options, as paper size, resolution, etc."
如果打印机需要的PPD文件 不 在CUPS中, 那么:
现在CUPS已经安装好了, 有很多选择可以供你安装一个打印机实例. 一直以来你都可以选用非常可靠的命令行的方式. 同样，Gnome和KDE也都提供了实用的用户界面的配置工具. 为了让最广大的群众方便地配置成功，本文将解释CUPS提供的web界面.
如果你要连接到一个网络打印机而不是直接连到你机器上的, 你应该先读一读这一页 CUPS printer sharing. 在GNU/Linux系统间共享打印机非常简单，只需要少许配置，而在linux和Windows之间共享打印机就需要多费一些功夫了.
根据你使用的不同内核，这些步骤不一定是必要的. 当你连上打印机时内核会自动加载合适的模块. 用
tail 命令 (后文会说明) 看看打印机是否已经连上了。
USB printer users may need to blacklist the
usblp module. Keep in mind that there seems to be a lot of uncertainty regarding blacklisting
usblp, as some USB printers, including some Canon and Epson printer series, are not recognized without it. Several user reported issues with Samsung printers when using
cups with blacklisted
usblp module, the solution was to re-enable
usblp and install
cups-usblp from aur instead of regular
cups package (https://bbs.archlinux.org/viewtopic.php?pid=778104)
To blacklist the module:
Custom kernel users may need to manually load the
usbcore module before proceeding:
# modprobe usbcore
Once the modules are installed, plug in the printer and check if the kernel detected it by running the following:
# tail /var/log/messages.log
If you're using
usblp, the output should indicate that the printer has been detected like so:
Feb 19 20:17:11 kernel: printer.c: usblp0: USB Bidirectional printer dev 2 if 0 alt 0 proto 2 vid 0x04E8 pid 0x300E Feb 19 20:17:11 kernel: usb.c: usblp driver claimed interface cfef3920 Feb 19 20:17:11 kernel: printer.c: v0.13: USB Printer Device Class driver
If you blacklisted
usblp, you will see something like:
usb 3-2: new full speed USB device using uhci_hcd and address 3 usb 3-2: configuration #1 chosen from 1 choice
Parallel port printers
To use a parallel port printer the configuration is pretty much the same, except for the modules:
# modprobe lp # modprobe parport # modprobe parport_pc
Once again, check the setup by running:
# tail /var/log/messages.log
It should display something like this:
lp0: using parport0 (polling).
If you are using a USB to parallel port adapter, CUPS will not be able to detect the printer. As a workaround, add the printer using a different connection type and then change DeviceID in /etc/cups/printers.conf:
DeviceID = parallel:/dev/usb/lp0
It is convenient to have the system automatically load the kernel module every time the it starts up. To do so, use a text editor to open up
/etc/rc.conf and add the appropriate module to the
MODULES=() line. Here is an example:
MODULES=(!usbserial scsi_mod sd_mod snd-ymfpci snd-pcm-oss lp parport parport_pc ide-scsi)
Web interface and tool-kit
Once the daemon is running, open a browser and go to: http://localhost:631 (The localhost string may need to be replaced with the hostname found in
From here, follow the various wizards to add the printer. A usual procedure is to start by clicking on Adding Printers and Classes and then Add Printer. When prompted for a user-name and password, log in as root. The name assigned to the printer does not matter, the same applies for 'location' and 'description'. Next, a list of devices to select from will be presented. The actual name of the printer shows up next to the label ( e.g., next to USB Printer #1 for USB printers). Finally, choose the appropriate drivers and the configuration is complete.
Now test the configuration by pressing the Maintenance drop-down menu then Print Test Page. If it does not print and there is certainty regarding the correctness of applied settings, then the problem is most likely due to missing a proper printer driver.
A user-name and password will be required when administering the printer in the web interface, such as: adding or removing printers, stopping print tasks, etc. The default user-name is the one assigned in the sys group, or root (change this by editing
/etc/cups/cupsd.conf in the line of SystemGroup).
If the root account has been locked (i.e. when using sudo), it is not possible to log in the CUPS administration interface with the default user-name and password. In this case, follow these instructions on the CUPS FAQ. You might also want to read this post.
Remote access to web interface
By default, the CUPS web interface can only be accessed by the localhost; i.e. the computer that it is installed on. To remotely access the interface, make the following changes to the
/etc/cups/cupsd.conf file. Replace the line:
so that CUPS listens to incoming requests.
Three levels of access can be granted:
<Location /> #access to the server <Location /admin> #access to the admin pages <Location /admin/conf> #access to configuration files
To give remote hosts access to one of these levels, add an
Allow statement to that level's section. An
Allow statement can take one or more of the forms listed below:
Allow all Allow host.domain.com Allow *.domain.com Allow ip-address Allow ip-address/netmask
Deny statements can also be used. For example, if wanting to give all hosts on the 192.168.1.0/255.255.255.0 subnet full access, file
/etc/cups/cupsd.conf would include this:
# Restrict access to the server... # By default only localhost connections are possible <Location /> Order allow,deny Allow From localhost Allow From 192.168.1.0/255.255.255.0 </Location> # Restrict access to the admin pages... <Location /admin> # Encryption disabled by default #Encryption Required Order allow,deny Allow From localhost Allow From 192.168.1.0/255.255.255.0 </Location> # Restrict access to configuration files... <Location /admin/conf> AuthType Basic Require user @SYSTEM Order allow,deny Allow From localhost Allow From 192.168.1.0/255.255.255.0 </Location>
You might also need to add:
This should avoid the error: 426 - Upgrade Required when using the CUPS web interface from a remote machine.
Once you have CUPS setup on your Linux print server, sharing the printer with another Linux box is relatively easy. There are several ways to configure such a scenario, here we will describe the manual setup. On the server computer (the one managing and connecting to the printer) simply open up the /etc/cups/cupsd.conf file and allow access to the server by modifying the location lines. For instance:
<Location /> Order Deny,Allow Deny From All Allow From 127.0.0.1 Allow From 10.0.0.* </Location>
You will also need to make sure the server is listening on the IP address your client will be addressing. Add the following line after "Listen localhost:631":
Add the IP address of the client computer by doing Allow From client_ip_address. After you make your modifications, you will want to restart CUPS by doing:
# /etc/rc.d/cupsd restart
On the client side, open up /etc/cups/client.conf and edit the ServerName option to match the ip address or the name of your server. For instance I named my server beast and have entry in my hosts file to point to it. So in my client.conf file, I just edited this line Factory: I did not have to do this step with cups 1.3.7. Going to localhost:631 on the client and then manage printers works fine without ever creating this file.:
Next, run the following command to update the client computerFactory: Same as the previous step... I did not have to do this.:
You should see something like this:
ml1250 is ready no entries
There are more configuration possibilities including an automatic configuration which are described in detail on http://localhost:631/sam.html#CLIENT_SETUP (this link works on your printer server). Factory: This link brings the user to a "404 Not Found" page.
when prompted for username and password use root to access then follow the instructions from here http://www.digitalhermit.com/linux/printing/ if its a TCP/IP printer use Jetdirect
That's it for Linux to Linux printer sharing.
Linux 共享给 Windows
If you are connected to a Windows print server (or any other Samba capable print server), you can skip the section about kernel modules and such. All you have to do is start the CUPS daemon and complete the web interface as specified in section 3.3 and 3.4. Before this, you need to activate the Samba CUPS backend. You can do this by entering the following command:
# ln -s `which smbspool` /usr/lib/cups/backend/smb
Note that the symbol before is ` (underneath the ~ on a standard US keyboard) and not '. After this, you will have to restart CUPS using the command specified in the previous section. Next, simply login into the CUPS web interface and choose to add a new printer. For device, there should be an option that says something to the effect Windows Printer Via Samba near the button of the device list. For the device location enter:
Or without a password:
Make sure that the user actually has access to the printer on Windows computer. Select the appropriate drivers and that's about it. If the computer is located on a domain, make sure the username includes the domain:
Note: if your network contains many printers use "lpoptions -d your_desired_default_printer_name" to set your preferred printer
Note: I, thepizzaking, was having 'NT_STATUS_ACCESS_DENIED' errors and to fix them I needed to use a slightly different syntax:
Windows 共享给 Linux
有时，我们需要允许一台装windows系统的电脑连接到一台linux电脑上.方法有很多种，最常用的就是使用Samba.编辑samba配置文件 /etc/samba/smb.conf ，使其允许控制打印机。修改后的smb.conf 看起来如下:
[global] workgroup = Heroes server string = Arch Linux Print Server security = user [printers] comment = All Printers path = /var/spool/samba browseable = yes # to allow user 'guest account' to print. guest ok = no writable = no printable = yes create mode = 0700 write list = @adm root neocephas
[ML1250] comment = Samsung ML-1250 Laser Printer printer=ml1250 path = /var/spool/samba printing = cups printable = yes printer admin = @admin root neocephas user client driver = yes # to allow user 'guest account' to print. guest ok = no writable = no write list = @adm root neocephas valid users = @adm root neocephas
Please note that in my configuration I made it so that users must have a valid account to access the printer. To have a public printer, set guest ok to yes, and remove the valid users line. To add accounts, you must setup a regular Linux account and then setup a Samba password on the server. For instance:
# useradd neocephas # smbpasswd -a neocephas
After setting up any user accounts that you need, you will also need to set up the samba spool folder:
# mkdir /var/spool/samba # chmod 777 /var/spool/samba
The next items that need changing are /etc/cups/mime.convs and /etc/cups/mime.types:
# The following line is found at near the end of the file. Uncomment it. application/octet-stream application/vnd.cups-raw 0 -
# Again near the end of the file. application/octet-stream
The changes to mime.convs and mime.types are needed to make CUPS print Microsoft Office document files. Many people seem to need that.
After this restart your Samba daemon:
# /etc/rc.d/samba restart
Obvious, there are a lot of tweaks and customization that can be done with setting up a Samba print server, so I advise you to look at the Samba and CUPS documentation for more help. The smb.conf.example file also has some good samples to that you might want to look at.
Windows 2000 and Windows XP to Linux
For the most modern flavors of Windows an alternative way of connecting to your Linux printer server is to use the CUPS protocol directly. The Windows client will need to be using Windows 2000 or Windows XP. Make sure you allows the clients to access the print server by editing the location settings as specified in section 4.1.
On the Windows computer, go to the printer control panel and choose to Add a New Printer. Next, choose to give an url. For the url type in the location of your printer:
where host_ip_address is the Linux server's IP address and printer_name is the name of the printer you are connecting to. After this, install the printer drivers for the Windows computer. If you setup the CUPS server to use its own printer drivers, then you can just select a generic postscript printer for the Windows client. You can then test your print setup by printing a test page.
Others to Linux, Linux to others
More information on interfacing CUPS with other printing systems can be found in the CUPS manual, e.g. on http://localhost:631/sam.html#PRINTING_OTHER
Alternative CUPS Interfaces
A Pygtk CUPS configuration program from Red Hat is also available in the "community" repository:
pacman -S system-config-printer
You can also try hal-cups-utils, also from community:
pacman -S hal-cups-utils
KDE users can modify their printers from the Control Center. Refer the KDE documentation for more information on how to use the interface.
There is also gtklp for handling print jobs. It is in the "extra" repository.
pacman -S gtklp
PDF Virtual Printer
A nice little package that I submitted to the incoming folder (ftp://ftp.archlinux.org/incoming) is CUPS-PDF. This package allows one to setup a virtual printer that will generate a PDF from anything sent to it. For example, I wrote this document in AbiWord and then printed it to the Virtual Printer which generated a pdf in my /var/spool/cups-pdf/neocephas folder. Obviously, this package is not necessary, but it can be quite useful. After downloading the package from the ftp server and installing it, you can set it up as you would for any other printer in the web interface. Select Virtual PDF Printer as the device and choose Postscript -> Postscript Color Printer for the drivers.
Here is a listing of websites that may be of use to you:
- Official CUPS documentation on your computer http://localhost:631/help.html
- Official CUPS Website - http://www.cups.org/
- Linux Printing - http://www.linuxprinting.org/
- Tips and Suggestions on common CUPS problems - http://home.nyc.rr.com/computertaijutsu/cups.html
- Gentoo's Printing Guide - http://www.gentoo.org/doc/en/printing-howto.xml
- Arch Linux User Forums - http://bbs.archlinux.org/
- Minolta toner cartridge
- Tektronix print cartridge
- Pitney Bowes ink cartridge
This section is dedicated to specific problems and their solutions. If you managed to get some unusual printer working, please put the solution here.
Printing does not work/aborts with the HP Deskjet 700 Series Printers.
- The solution is to install pnm2ppa printer filter for the HP Deskjet 700 series. Without this the print jobs will be aborted by the system. A PKGBUILD for pnm2ppa can be found in AUR.
Getting HP LaserJet 1010 to work
I had to compile ghostscript myself because ESP gs in rep was 7.07 and had not fixed some bugs like ESP 8.15.1 had. I never downloaded 'foomatic' in rep. I think that is an old package.
$ pacman -Qs cups a2ps psutils foo ghost local/cups 1.1.23-3 The CUPS Printing System local/a2ps 4.13b-3 a2ps is an Any to PostScript filter local/psutils p17-3 A set of postscript utilities. local/foomatic-db 3.0.2-1 Foomatic is a system for using free software printer drivers with common spoolers on Unix local/foomatic-db-engine 3.0.2-1 Foomatic is a system for using free software printer drivers with common spoolers on Unix local/foomatic-db-ppd 3.0.2-1 Foomatic is a system for using free software printer drivers with common spoolers on Unix local/foomatic-filters 3.0.2-1 Foomatic is a system for using free software printer drivers with common spoolers on Unix local/espgs 8.15.1-1 ESP Ghostscript
I also had to set LogLevel in /etc/cups/cupsd.conf to debug2 before i saw that I missed some "Nimbus" fonts. Then I had to rename & put them where the log told me to. Some fancy google searching had to be applied, example: http://www.google.com/search?q=n019003l+filetype%3Apfb since the fonts turned out to be proprietary (i'm sure windows comes with these default). Nevertheless after downloading them(about 7 fonts) and putting them in the correct folder printing started working.
Before that i were getting all the errors said here: http://linuxprinting.org/show_printer.cgi?recnum=HP-LaserJet_1010 'Unsupport PCL' etc...
I'm sure it could have worked with ESP gs 7.07 too(in rep) if i was smart enough to turn on DebugLevel2 sooner :/ UPDATE: yeah it did... maybe this info is useful for someone else though.. sorry for the inconvenience.
Getting HP LaserJet 1020 to work
After a lot of tries with hplib and gutenprint I finally found the solution to get my printer HP Laserjet 1020 printing.
First of all you only need to install cups and ghostscript. Then follow the link on http://www.linuxprinting.org/show_printer.cgi?recnum=HP-LaserJet_1020 to the http://foo2zjs.rkkda.com/ printer driver page and follow the install instructions. Log in as root. After you downloaded the package and extracted the archive, change into the foo2zjs directory. Now you can follow the original installation instructions with a minor modification to change the userid for printing:
$ make $ ./getweb 1020
Open the Makefile
$ nano Makefile
and search for the line
and modify it to
then continue with the script
$ make install $ make install-hotplug $ make cups
Or you can use the package foo2zjs from AUR and modify the PKGBUILD: change the line
(or if you're setting another printer change this line to what you need).
As a last step add and configure the printer in the CUPS manager. The printer should be recognized automatically. It works fine for root and all users. When booting the operating system, the printer is initialized and indicates its working.
Printer connected to an Airport Express Station
The first thing to do is to scan the airport express station. It seems that there are different addresses depending on the model.
[root@somostation somos]# nmap 192.168.0.4 Starting Nmap 4.20 ( http://insecure.org ) at 2007-06-26 00:50 CEST Interesting ports on 192.168.0.4: Not shown: 1694 closed ports PORT STATE SERVICE 5000/tcp open UPnP 9100/tcp open jetdirect 10000/tcp open snet-sensor-mgmt MAC Address: 00:14:51:70:D5:66 (Apple Computer) Nmap finished: 1 IP address (1 host up) scanned in 25.815 seconds
With my station the port is 9100. The airport station is accessed like an HP JetDirect printer. After, you can edit your printer.conf file in this way:
# Printer configuration file for CUPS v1.2.11 # Written by cupsd on 2007-06-26 00:44 <Printer LaserSim> Info SAMSUNG ML-1510 gdi Location SomoStation DeviceURI socket://192.168.0.4:9100 State Idle StateTime 1182811465 Accepting Yes Shared Yes JobSheets none none QuotaPeriod 0 PageLimit 0 KLimit 0 OpPolicy default ErrorPolicy stop-printer </Printer>
It should work. I had a few problems. There were resolved by removing foomatic and installing foomatic-db, foomatic-db-engine, foomatic-db-ppd instead.
Performing Utility Functions on Epson Printers
Here we explain how to perform some of the utility functions such as nozzle cleaning and nozzle checks on Epson printers. We will use the escputil utility, which is part of the gutenprint package.
There is a man page ("man escputil") that provides pretty good information, but it does not include necessary information on how to identify your printer. There are two parameters that can be used. One is --printer; what it expects is the name you used to identify your printer when you configured it. The other is --raw-device. What this option expects is is something beginning with "/dev". If your printer is a serial printer, and the only serial printer, it is "/dev/lp0". If it is an usb printer, it is "/dev/usb/lp0". If you have more than one printer, they will have names ending in "lp1", "lp2", etc.
- To clean the printer heads:
escputil -u --clean-head
- To prints the nozzle-check pattern, allowing you to verify that the previous head cleaning worked. (Or to determine that you need to clean the heads)
escputil -u --nozzle-check
If you want to perform an operation that requires 2-way communication with a printer, you must use the "--raw-device" specification, and your user must root or be a member of the group "lp".
- The following is an example of getting the printer's internal identification:
sudo escputil --raw-device=/dev/usb/lp0 --identify
- To prints out the ink levels of the printer:
sudo escputil --raw-device=/dev/usb/lp0 --ink-level
This is a printer status monitor which enables to get the remaining ink quantity, to print test patterns, to reset printer and to clean nozzle. It use an intuitive graphical user interface. Package can be downloaded from AUR.
Another Source for Printer Drivers
On http://www.turboprint.de/english.html is a really good printer driver for many printers not yet supported by Linux (especially Canon i*). The only problem is that high-quality-prints are either marked with a turboprint-logo or you have to pay for it... It's not Open-Source.
As a result of upgrade
Error with gnutls
After updating, if you get something like :
/usr/sbin/cupsd: error while loading shared libraries: libgnutls.so.13: cannot open shared object file: No such file or directory
You need to update gnutls:
pacman -S gnutls
In addition, in /etc/cups, there will be a file named cupsd.conf.pacnew. Rename it cupsd.conf.
All jobs are "stopped"
After updating CUPS, if all jobs sent to the printer become "stopped", delete the printer and add it again. Using the CUPS web interface (http://localhost:631), go to Printers > Delete Printer.
Note: If you don't remember your printer's settings, go to Printers > Modify Printer. Copy down the information displayed, click 'Modify Printer' to proceed to the next page(s), etc.