Troubleshooting GCP Issues

Note: Google announced that Google Cloud Print, their cloud-based printing solution that has been in beta since 2010, will no longer be supported as of December 31, 2020. We recommend you use PaperCut Mobility Print instead. If you’re currently using GCP, there is also a useful article on How to migrate from GCP to Mobility Print.

Q What version of PaperCut am I running?

Check that you’re running the latest version of PaperCut Since Google’s own Cloud Print product is still in Beta, there may be bug fixes and updates included with recent releases of the PaperCut Application Server and Print Provider - check the Release History page to see if you’re running the latest version, and to see if there have been any recent Google Cloud Print changes.

Q How do I find GCP jobs in PaperCut?

You can see jobs printed through a PaperCut Google Cloud Print printer in the PaperCut Job Log. Go to the web admin interface in Printers : Job Log. “Google Cloud Print” (without the quotation marks) appears in the Attribs. column for the job.

A GCP job in PaperCut Job Log

Q What do I check if the GCP jobs are logged as the wrong user?

We sometimes see this happen if the printers were published using the Google Cloud Print Connector or Chrome browser, instead of PaperCut’s implementation of Google Cloud Print. When this happens, all of the jobs from GCP will be charged to the SYSTEM account (or whatever service account that the Google Cloud Print Connector is running as).

If this is happening, make sure you have enabled Google Cloud Print in PaperCut in the Mobile & BYOD section, then select a printer in PaperCut, and on the Summary tab choose “Publish to Google Cloud Print”. There will now be a link to manage that printer in the Google Cloud Print web interface and share it out with your users.

To verify that the printer is being shared from PaperCut, log into the Google Cloud Print management interface, select a printer, choose Details, then expand the Advanced Details. A printer published by PaperCut to Google Cloud print will have the tag “pc_server_build” followed by a build number like the screenshot below. If the tag “pc_server_build” number is missing, then the printer has not been published to Google Cloud Print using PaperCut.

If the printer does not have this tag, then double check the steps in how to set up Google Cloud Print in the manual to make sure the printers have been published correctly.

Q Jobs are stuck as ‘In progress’ - what can I check?

Some customers using Securly for Web Filtering, have noticed that intermittently jobs submitted via Google Cloud Print won’t print, and will have a status of “In Progress”. When checking the error log there should be messages “ Failed to download job… [the URL] returned a response status of 426 null”. Securly has a documented workaround for this issue, which is to install their trusted certificate in the Keystore so that they can monitor this web traffic (like a man-in-the-middle attack).


Q How do I debug connectivity issues?

The Application Server has to be able to make connections to Google Cloud Print services as detailed in the relevant section of our User Manual. Please check our Google Cloud Print Requirements carefully to ensure that your environment meets our specifications.

Check that the necessary ports on your firewall are opened up as detailed in the Firewall Configuration - Ports Used by PaperCut NG and PaperCut MF Knowledge Base article, particularly TCP port 5222. From the Application Server (not your own workstation), open a Terminal or Command Prompt session, and type the following command:

telnet 5222

On macOS you should see the following result, if everything is okay:

Mac Telnet Terminal

On Windows, you should instead see this:

Windows Telnet Terminal

Note that if you get a message saying that Telnet does not exist, then you may need to enable/install Telnet on your server. On Windows, this is done as per the Install Telnet Client Microsoft TechNet article. Telnet was removed from the High Sierra release of macOS. One method to install it is to first install Homebrew, and then follow the instructions found here to use Homebrew to download the Telnet binary.

Q What if my GCP printers are showing as ‘offline’?

Take a look at Troubleshooting GCP printers showing as offline

Q What security concerns are there?

Another thing to consider was something brought up by one of our educational customers concerning network security. At one point a packet shaping implementation had been put in place to intercept XMPP/Jabber traffic in an effort to prevent inappropriate content sharing between students. XMPP happens to be the same protocol that Google Cloud Print uses to perform printer discovery and authentication management with PaperCut. What we learned from this scenario is that If XMPP is traffic is being restricted, then PaperCut will not be able to correctly do its printer discovery and authentication management. In this case the symptom was that the customer had a persistent issue with their Google Cloud Printers showing offline.

Q How do I distinguish PaperCut GCP printers from other GCP printers

There are ways of publishing a printer in GCP other than with PaperCut. e.g. Google Chrome allows you to publish printers on GCP. PaperCut may track jobs from these non-PaperCut GCP Printers. e.g. PaperCut may be tracking the printers that Google Chrome publishes to GCP. You can distinguish PaperCut GCP printers from those published by Google Chrome by setting a naming template with the PaperCut web admin Config Editor:

Go to Options : Config Editor Edit value of “” e.g. PC__ Press the Update button

This will make the PaperCut GCP printer start with “PC__”. e.g. If the printer name is “Physics Printer” then it will appear in GCP as “PC_Physics Printer”. If this printer was also published to GCP by Google Chrome then it would appear as “Physics Printer”.

Another way to check whether a GCP printer is published by PaperCut is to go to the printer in the PaperCut web admin interface Printers : Printer List : <Printer name>: Printer Details then go the “Google Cloud Print” section and click on the “Manage sharing in Google Cloud Print” link.

If you want to check id a CGP printer was published through PaperCut then find your printer in and select “Advanced Details”. PaperCut GCP printers will have a pc_server_build tag.

Q What if I’m still having issues with GCP?

If you have checked all the items above, and you’re still seeing issues please follow these steps:

  • Enable debug mode in the App Server as detailed on the Application Server Debug page
  • Additionally check the ‘Enable detailed logging for Google Cloud Print’ box under Options → Advanced → Diagnostics
  • Restart the App Server if possible, or re-publish printers that you’re having issues with, or send a test job through the system to capture the process that you’re seeing difficulties with in debug mode

Please then send an email to us through the Admin console’s ‘About’ tab → Support Info → Email Support. Please include:

  1. Version and build number of PaperCut
  2. Debug logs as detailed in the KB article above
  3. Username/email address of the user sending the test print job / Printername of the printer that you’re testing with, or any other specific test information that we can use to narrow down the area of the logs to look in.

Categories: Troubleshooting Articles, Google Cloud Print

Keywords: GCP, Android, google printer hosting, spooler service, windows queue, chromebook, byod, troubleshoot