The PrintNode Client's list of printers will be the same as what is reported by the operating system. On Windows you can view it by looking at Devices and Printers. On mac OS / OS X and Linux you can view it by running

lpstat -p

on the command line or via the CUPS web interface at https://localhost:631.

The list of printers the PrintNode Client has detected is visible on the Printers tab in the PrintNode Client's UI. After adding a printer it takes around three seconds to be detected on Windows and three to ten seconds on macOS / OS X and Linux.

• Only one instance of the PrintNode Client runs regardless of how many active user sessions there are on a given machine (this helps avoid certain issues such as duplicate prints).
• The end user does not have access to the desktop app interface, which makes them less likely to break something.
• It is possible to manage the PrintNode Client remotely through the PrintNode Client's web API.

• The PrintNode Client runs as the LocalSystem account, so it doesn't use the default printer settings of regular users.
• The end user does not have access to the desktop app interface, which makes it more difficult to provide support if something goes wrong.

• USB scales which implement the USB HID standard. This covers a wide variety of scales in use today. Your scale's manufacturer documentation should specify whether your scale supports USB HID. On Windows, you can also check by plugging in your scale, waiting for the operating system to install the driver and examining the driver's details.
• Scales which communicate over a serial interface. For details, please see this question.

• name and address;
• corporate registration information (e.g. company number, territory in which company is registered);
• short description of what your organisation does;
• short description of the software platform which will use PrintNode;
• at least one official point of contact (name and address / email address / telephone number);
• name and position of the individual who will execute the contract on behalf of your organisation.

• The operating system user under which the PrintNode Client is run needs to have permissions to access printers and the network.
• The PrintNode Client needs to be able to write to the user's home directory.

• If you submit a print job ("print job A") to our system, wait for a response from the API and then submit another print job ("print job B") to our system, then print job A will be printed before print job B.
• If you submit print job A to our system and then submit print job B before you have received an API response for print job A, then they could be printed in either order.

• C:\Users\[your user name]\.printnode\printnode\10\logs (in Windows, when run as a desktop application)
• C:\Windows\SysWOW64\config\systemprofile\.printnode\printnode\10\logs (in Windows, when run as a Windows Service)
• $HOME\.printnode\printnode\10\logs (in macOS / OS X and Linux)

• Digitally signing all of our executables.
• White-listing our software with the anti-virus vendors (some are more responsive than others).
• Working to remove / rewrite components that look suspicious to the anti-virus software.

• Reconfigure the Windows Service to run under a different user account, and change the default printer settings of that account. If you do this, ensure that the password for that account does not expire.
• Change the default printer settings of the LocalSystem account. You need to modify the Windows Registry for that. Note that modifying the Windows Registry can cause serious harm and should only be attempted with great care. The steps to follow are:
• Modify the default settings of your printer, using the standard Devices & Printers functionality.
• Run the registry editor (regedit.exe) and export the key
  
  HKEY_CURRENT_USER\Printers\DevModePerUser
  
  into a .reg file.
• Modify the .reg file so line 3 says:
  
  [HKEY_USERS\S-1-5-18\Printers\DevModePerUser]
  
  (S-1-5-18 is the security identifier of the LocalSystem account)
• Run the modified .reg file; confirm that you want to continue if asked. You should receive a message saying The keys and values contained in [your modified .reg file] have been successfully added to the registry.
• Restart the PrintNode Windows Service.
• Go to http://localhost:8888/printers to confirm that the new settings have been applied.

1. Change the default printing backend to Engine6 on Windows or Engine7 on macOS – you can do this by using the drop-down menu in the top-right corner of the Printers tab.
2. Perform the print.

1. Log into the CUPS web interface by pointing a browser to https://localhost:631. You may need to enable this functionality by running a console command. Follow instructions as they appear.
2. After logging in, go to Administration -> Manage printers and select your printer.
3. In the Administration drop-down box, select Modify printer.
4. Click through the wizard until you are presented with options to select your printer's make and model. Choose the appropriate make and model from the options provided. Note that there may be more than one model which corresponds to your printer. You may have to try more than one selection.
5. Finish clicking through the wizard.
6. After clicking through the wizard, you will be returned to the printer page. Select Print test page from the Maintenance drop-down list. If a test page is successfully printed, the printer is ready to use with PrintNode. If not, follow this sequence of instructions again, but at step 4 try choosing a different model.

• Make sure that you set the correct credentials (for example, when using an API Key, ensure that it belongs to the correct PrintNode account).
• Refresh the list of printers.

• Scales which connect via USB but use a serial communication protocol. If you're using such a scale, please see this question.
• Scales which implement the USB HID standard. To check whether your scale is one of these, follow the instructions below.

• Open Control Panel.
• Click on Devices and Printers under the Hardware and Sound section.
• Right-click your scale and click Properties.
• Go to Hardware tab and look for HID-compliant device.

• Switch your scale to a different USB port.
• Disable USB power saving mode.
• Try connecting your scale as the only USB device attached to the computer.

• Unchecking the Enable Scales checkbox in the Scales tab of the PrintNode Client.
• Disabling scales completely.

• We never sell your personal information to any third party, or share it for marketing purposes.
• We use a third-party service to send emails (legitimate business emails; not spam), so to send an email to you, we have to send your email address to the third-party service. They are GDPR-compliant and they will not use your email address for any other purpose.
• We collect, store and process only the data we require to provide you with the service you have signed up for, and we keep it only for as long as we need to.
• When you send your documents through our service to be printed, we do not look at their contents and we do not perform analytics, keyword searches, deep learning, text mining, feature extraction, machine learning or any other kind of interpretation or information extraction on them. We don't know what's in your documents and we don't want to know.

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