On October 12, 2021, Microsoft released its monthly cumulative updates for Windows 10 to fix bugs and vulnerabilities.
However, after installing the Windows 10 KB5006670 and Windows 11 KB5006674 updates, Windows customers have started experiencing network printing issues.
Upon installing these updates, users of both Windows 10 and Windows 11 have been unable to print on their network printers, and are experiencing the following errors when connecting to a remote printer shared on a Windows print server:
- 0x000006e4 (RPC_S_CANNOT_SUPPORT)
- 0x0000007c (ERROR_INVALID_LEVEL)
- 0x00000709 (ERROR_INVALID_PRINTER_NAME)
The following Windows platforms are affected by the issue:
- Client: Windows 11, version 21H2; Windows 10, version 21H1; Windows 10, version 20H2; Windows 10, version 2004; Windows 10, version 1909; Windows 10, version 1809; Windows 10 Enterprise LTSC 2019; Windows 10 Enterprise LTSC 2016; Windows 10, version 1607; Windows 10 Enterprise 2015 LTSB; Windows 8.1; Windows 7 SP1
- Server: Windows Server 2022; Windows Server, version 20H2; Windows Server, version 2004; Windows Server, version 1909; Windows Server, version 1809; Windows Server 2019; Windows Server 2016; Windows Server 2012 R2; Windows Server 2012; Windows Server 2008 R2 SP1; Windows Server 2008 SP2
According to Microsoft, the printer connection issues described in this issue are specific to print servers that are more commonly found in enterprises and organizations.
The Redmond giant said it is working on a resolution that will allow print clients to establish RPC packet privacy connections to print servers using RPC over SMB.
Meanwhile, users can mitigate the issue on affected print servers that meet the following prerequisite:
“Print clients must have installed a Windows update released on or after January 2021 before the print server has installed” the October 2021 updates.
If the workaround requirements are met, users need to ensure that network security and VPN solutions allow print clients to establish RPC over TCP connections to print server over the following port range.
- Default start port: 49152
- Default end port: 65535
- Port Range: 16384 ports
Users can also refer to the below mentioned articles for further guidance: