Cause

This problem occurs because the printer port does not begin with COM, LPT, or USB. Ports such as DOT4, etc. will not be redirected.

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Resolution

Force all ports on the client computer to be filtered for redirection. To perform this, create a DWORD value named FilterQueueType under HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\Default\AddIns\RDPDR and set the value to FFFFFFFF.