What is the 'could not connect to printer error 0x00000bcb' and what are its primary causes?

The error 0x00000bcb, often accompanied by 'could not connect to printer', is a common Windows error indicating a problem establishing a connection to a network or shared printer. It frequently manifests as 'RPC_S_SERVER_UNAVAILABLE'. Its primary causes are often related to security updates from Microsoft (like KB5005573, KB5006670, KB5007186, KB5008212, KB5009596) that introduced stricter security measures for Point and Print vulnerabilities, especially concerning remote procedure call (RPC) connections and driver installations from print servers. Incompatible or unsigned printer drivers and issues with the print spooler service can also trigger this error.