Thursday, July 21, 2011

Windows 7 Explorer Hangs Interminably On Network Copy to 2008 R2 Server

Quick Description:  Windows explorer hangs copying large files at “discovering” and never returns when copying from Windows 7 to a Windows 2008 R2 network location.  Attempting to cancel, or close the dialog will switch the dialog to say it is copying with n minutes left, but no progress is actually made.
Solution:  As referenced in KB951037 disabling TCP Chimney Offload instantly solved the problem for me.
From an administrator command prompt type:
netsh int tcp set global chimney=disabled

Update:  This can also a problem with Symantec Enterprise Protection 11.  My feelings about the product notwithstanding, many company domain policies will allow you temporarily kill the service (services.msc) while you perform a specific task.


  1. I have been dealing with this problem for days and behold SEP 11 was the culprit. I uninstalled SEP on the client side and the problem was gone. I ended up having to build a new install package with just Anti-Virus & Anti-Spyware and the problem is now resolved. Thank you for showing me the path.

  2. Thanks Caroline,
    SEP11 was the cause here also.

  3. SEP 11 Caused it here too..thank you.