Winsock Applications May Timeout or Fail with an Error

• Microsoft Windows NT Workstation version 4.0
• Microsoft Windows NT Server version 4.0

SYMPTOMS

Winsock applications running on the specified version of Windows NT Server or Workstation may fail with timeout errors, report incomplete data received, or report some other error. The failures seen include errors indicating that the remote system is no longer available or that incorrect results have been received from the remote system. This problem has been seen with socket applications running on Macintosh client systems connecting to Windows NT Server using the AppleTalk protocol.

CAUSE

When a Winsock application calls one of the Winsock send APIs (Send, WSASend, and so on), one of the parameters passed to the API is the amount of data to be sent. If for any reason the Winsock driver, Afd.sys, could not send the total amount on a nonblocking socket in a single data packet, Afd.sys would incorrectly report the total bytes sent to the application. There may be other symptoms because an incorrect response will have an undetermined effect on the application.

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 4.0 with Service Pack 2. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K