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Thank you for providing an update and the troubleshooting steps you have already completed.
Based on your description, the issue may be related to the printer queue, driver registration, or how Windows applications are detecting the installed printer. Since you have already restarted the computer, reinstalled the printer, restarted the Print Spooler service, tested Windows Protected Print Mode, and confirmed that there is no option to set the printer as the default, please try the following additional checks:
1. Verify whether the printer can print a Windows test page
- Go to Settings > Bluetooth & devices > Printers & scanners.
- Select the printer, open Printer properties, and choose Print Test Page.
- If the test page does not print, the issue is likely related to the printer driver or printer configuration rather than Word.
2. Check whether the printer appears in Control Panel
- Open Control Panel > Devices and Printers.
- Confirm whether the printer appears there or only under Settings > Printers & scanners.
- If multiple instances of the same printer exist, remove any old, offline, or duplicate entries and keep only the active printer queue.
3. Reinstall the manufacturer's printer driver
- Remove the printer from Windows.
- Download and install the latest compatible driver directly from the printer manufacturer's support website.
- If the printer is currently using a Microsoft IPP, WSD, or Class Driver, installing the manufacturer's driver may help resolve an incomplete or corrupt driver registration. In some cases, Windows can detect a printer and display it in Settings, but applications cannot enumerate it correctly.
4. Test from multiple applications
- Check whether the printer appears in Notepad, Paint, Adobe Reader, or other applications.
- If it is missing from all applications, the issue is more likely related to the Windows printing subsystem or printer driver.
- If it is missing only from Word, consider repairing Microsoft Office from Settings > Apps > Installed apps > Microsoft 365 > Modify.
5. Test with a new local Windows user account
- Create a new local Windows user account and sign in.
- Check whether the printer appears when printing from applications.
- If it works in the new account, the issue may be related to the original user profile.
References: My Print button and some printer settings aren't available | Microsoft Support
Fix printing problems in Word, Excel, or other apps | Microsoft Support
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