On our Windows Server 2022 Remote Desktop Session Host servers, the Settings app initially shows only the printers installed for the current user. After a few seconds, however, Printers & scanners fills with hundreds of queues from our Windows Server 2019 print server. The queues include printers published in Active Directory as well as ones that are not, and they are only being displayed—not actually installed. Get-Printer still shows only the local printers.
We have ruled out normal printer deployment, Group Policy printer mappings, login scripts, HKCU printer connections, Universal Print, and WSD-discovered physical printers. We also disabled Function Discovery Provider Host, Function Discovery Resource Publication, SSDP Discovery, UPnP Device Host, and related network-discovery firewall rules. The behavior still occurs, including on a drained RDS server with only a test session logged in.
Client printer redirection is enabled in our environment, but disabling it does not change the behavior, and the enumerated queues are not marked as redirected. Some entries appear duplicated or associated with another user's SID. Is there a policy or setting that disables printer browsing or enumeration in the modern Settings app, so users see only printers actually installed in their session?
4 Answers
There are printer-related policies under Computer Configuration > Administrative Templates > Printers called “Add printer wizard - network scan page (managed network)” and “Add printer wizard - network scan page (unmanaged network).” Enabling them and setting their options to 0 can stop the Add device workflow from displaying printers discovered on nearby visible print servers, leaving the manual-add option instead.
That said, this may only affect the Add printer wizard. It does not necessarily prevent the modern Printers & scanners page from populating its list before the user clicks Add device, so it may not address this exact symptom.
The print server itself is using ordinary shared queues on TCP 9100 with manufacturer drivers, so the queue type alone should not make every printer install on the RDS host. Since both published and unpublished queues appear, this sounds more like browsing the print server than Group Policy deployment. I would compare the timing against recent Windows cumulative updates and test the same account on a fully patched and previously patched RDS host; the modern Settings app may be discovering visible Windows print servers independently of Get-Printer and the usual discovery services.
This can be related to RDS printer state leaking between sessions. A printer added by one user—manually or through automation—may show up as a broken or duplicate queue for other users on the same host. Checking the affected entries for the owning user or SID can reveal that they are stale per-user printer objects rather than real installations.
That seems plausible because several entries are duplicates and some show a SID belonging to a different user. However, the behavior also occurs on a clean, drained server with only my test account connected, so it may be a symptom rather than the original cause.
Client printer redirection and Easy Print are worth checking, especially if users connect from multiple locations. You can test the policy under Remote Desktop Services > Remote Desktop Session Host > Printer Redirection, including “Do not allow client printer redirection” and the setting that prefers the Remote Desktop Easy Print driver. Also check for disconnected sessions and stale redirected queues.
In this case, though, redirection does not appear to be the explanation: the queues are not labeled as redirected, the issue remains when redirection is disabled, and it happens with no abandoned sessions. The remaining suspect is Windows' printer discovery behavior in the modern Settings experience, possibly combined with stale per-user printer data or a recent OS update.
We use redirected printing, but disabling it does not stop the enumeration. The same result occurs on a server with no disconnected users, so I’m focusing on the Settings app’s discovery behavior rather than Easy Print.
I tested those policies, but they made no difference. The unwanted queues appear before Add a printer is selected, so this looks like a separate enumeration path.