XADM: Store Stops Responding with High CPU Usage

• Microsoft Exchange Server, version 4.0
• Microsoft Windows NT Workstation versions 3.51 and 4.0
• Microsoft Windows NT Server versions 3.51 and 4.0

SYMPTOMS

The Microsoft Exchange Server Information Store service may appear to stop responding with 90 to 100 percent CPU time. Any clients may also stop responding; the cursor turns into the "wait" symbol (hourglass). When this problem occurs, stopping and starting the Information Store reduces the CPU usage to normal levels and frees up the clients.

CAUSE

A Microsoft Exchange Server Information Store thread loops forever on a Winsock recv() function. Winsock recv() is returning zero bytes received because the remote computer has gracefully disconnected the connection.

The reason for the problem is that the Information Store thread is stuck in a remote procedure call (RPC). The RPC routine is continually calling the Winsock recv() function because it is returning zero bytes read, which is an error.

RESOLUTION

To resolve this problem, download and install the appropriate file:

Windows NT 3.51

This hotfix has been posted to the following Internet location:

   ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT351/
   hotfixes-postSP5/rpc-fix

Windows NT 4.0

This hotfix has been posted to the following Internet location:

   ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40/
   hotfixes-postSP2/rpc-fix

Microsoft has confirmed this to be a problem in Windows NT version 3.51 and 4.0.

A supported fix is now available, but is not fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information.