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Webconverger utilises CUPS 1.5 which auto-detects CUPS <1.6 servers using "BrowsePoll" for CUPS Browsing for sharing and discovery. This "auto setup" feature is removed in CUPS 1.6.

Holding down the [Control] and [p] keys on your keyboard gives you the printing dialog. Or you can use the showprintbutton API to show a print icon to your users.

Mozilla Firefox printing guidelines can help you improve prints.

If you do not see your printer in that dialog or you just see "Print to File", your print server is not correctly configured.

So unfortunately the user experience of just using detected "auto setup" printers is no longer supported in CUPS. You now need to "Add printer..." up front, and hence we have introduced the printer= API for you to do this.

Helping us support you

For our customers, please print out the "Printer Settings" report and send it to us (a good capture from your mobile is usually sufficient) together with your printer query.

printer= API

the printer= API has syntax like so:

printer=printer name,device URI,driver URI

For example a Ricoh Aficio SP 4310N with PPD on IP might be setup like so:


Instead of specifying a remote PPD, you should ideally use the internal (generic) drivers: "drv:///sample.drv/generpcl.ppd" or "drv:///sample.drv/generic.ppd".

For example a network printer named "helpdesk" with dns name printer is very likely to have "Laser printer" PCL support:


However if your printer supports PostScript, you might find using the "Generic PostScript Printer" driver drv:///sample.drv/generic.ppd result in better quality prints.

You can have multiple printer= lines and hence give your users several printers to print to.

Two typical printing configurations

Using a network printer

Buy a printer with a network port. These printers are generally more expensive and generally have IPP support built in. Some do not have an IPP print server or are simply buggy. So make sure you purchase it with a good exchange / refund policy.

Discovering the "device URI" can be alarmingly difficult. Usually socket://$PRINTER_IP_ADDRESS will probably work.

Using a CUPS server with (attached) printer shared upon it

Buy a printer and attach it to a MacOSX / Ubuntu / Windows PC. Proceed to install drivers and most importantly the CUPS print server software. Then configure the CUPS server to be shared upon the network.

Add your printer to the client using the printer= API, using the an appropriate device URI.

prefs= API to remove default header and footer

The prefs= API allows you to override Firefox preferences.

For example prefs= removes header/footer for the printer named 'Ricoh'.

Disable PDF.JS

A preference override such as:

pref("pdfjs.disabled", true);

Disables the default Mozilla PDF viewer, which should default to epdfview viewer. PDFJS has issues like:

Setting default paper type to A4

pref("print.postscript.paper_size", "A4");

Printing to a PDF file to a remote machine on your network


The cups-pdf package allows you to setup a "Virtual Print" server on your network that write out PDFs on your server's spool directory.

This is useful for archiving, debugging and allowing you to manually check what does and does not get printed.

Assuming you have a permissively configured CUPS server (not Webconverger, an Ubuntu install for example) with cups-pdf installed, you need to figure the IP address or name (e.g. of your print server, that can be accessed by your clients. To find the device URI of your CUPS printer, it's the "Queue Name" URL in the Administration Tab → Manage Printers, see the highlighted device URI screenshot.

Once you know the printer's device URI, you then setup your Webconverger clients like so:


On the print server, you should be able to see "Send-Document successful-ok" whilst viewing the log like so tail -f /var/log/cups/access_log.

Advanced debugging

Assuming you are running a Virtualbox instance, sharing a bridged adaptor. On the host with the Virtualbox on

sudo tcpdump -w /tmp/foo.pcap -s 0 -n -i wlan0 dst and not port 53
wireshark -r /tmp/foo.pcap

lpstat -t is a good way to list CUPS printers to see how they are configured on a running Webconverger system.