Semaphore Error After Disabling Write Behind Caching

ID: Q216795

The information in this article applies to:

Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

When you change the following registry subkey

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Rdr\Parameters
Value Name: UseWriteBehind
Data Type:  REG_DWORD
Data:       0 

on a computer running Microsoft Terminal Server and then try to copy a file to a remote share over the network, the following error message is displayed:

To Many Posts Were Made to a Semaphore.

This may occur when you run the Terminal Server console and when a client is connected to a Terminal Server Session, because both are copying files from the Terminal Server computer to a remote share.

CAUSE

This problem occurs because of a problem in the redirector, which manipulates an operating system semaphore.

WORKAROUND

To work around this problem:

Re-enable write behind caching by setting UseWriteBehind to 1.

-or-

Apply the hotfix mentioned below.

RESOLUTION

A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to systems experiencing this specific problem. If you are not severely affected by this specific problem, Microsoft recommends that you wait for the next that contains this fix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp


   Date       Time         Version   Size      File name   Platform
   ----------------------------------------------------------------
   02/14/99   11:10:00 PM  4.0       264,848   Rdr.sys     Intel
   02/14/99   11:09:50 PM  4.0       506,928   Rdr.sys     Alpha

Install the latest service pack for Windows NT server 4.0, Terminal Server Edition. Service pack 4 for Windows Terminal Server contains the fix for this bug.

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0 Terminal Server version SP4. This problem has been corrected in the latest U.S. service pack for Windows NT 4.0 Terminal Server version SP4. 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

Additional query words: Terminalsvr Semaphore

Keywords :
Version : winnt:4.0
Platform : winnt
Issue type : kbbug