PRB: Anti-virus Program May Cause Named Pipes Connection Problem

• Microsoft SQL Server, versions 6.0 and 6.5

SYMPTOMS

Anti-virus software running on client computers may cause Named Pipes connections to Microsoft SQL Server to fail. The client application may stop responding, take a long time, or sometimes receive error 231, "Connection Busy." On the SQL Server error log, error 17832 "Unable to read login packet" may be logged. Connections to SQL Server using a different network protocol work normally.

CAUSE

When the client application requests to open a pipe, and if the anti-virus software is configured to scan all files, the anti-virus software treats the pipe as a file, and attempts to scan it. This results in opening the pipe is a "deny all" mode that prevents the client software from reading or writing to the pipe while connected to the server. After the pipe is opened in this mode, the client is not able to send the login packet to the server. This results in raising error 17832 "Unable to read login packet" in the SQL Server error log.

Other Named Pipes connections from the same client fail because the pipe is already open in a "deny all" mode that prevents the usage of the same pipe by those connections. This scenario results in receiving error 231 "Pipe busy" or "Connection Busy."

WORKAROUND

To work around this problem, try the following suggestions:

• Configure the anti-virus software to scan program files only.
• Remove the anti-virus software and evaluate the SQL Server Named Pipes connection.
• Contact the anti-virus vendor for suggestions on configuring the software.