We had 2003 file server and every thing was fine. We moved to R2 and now W7 clients take long time to copy a file from the share.The same file a XP client copy instantly.

Do you have Symantec AV installed? If yes what is the version?

SEP 11.0.5000.329

This is a know issue with Symantec. Upgrade to RU6MP3 The kb http://www.symantec.com/business/support/index?page=content&id=TECH139768 has been updated. Symantec has released SEP RU6MP3, which states that SEP is now compatible with SMB2. Or Remove NTP from the client and this will resolve the issue.

Thanks for the reply.Upgrade doesn't look like a solution at this point of time , There are some custom build company s/w that work well with SEP. And i don't know with upgrade will they work or not. As with Symantec each update fix 10 bugs and creates another 10. Disabling the NTP could be a solution, Anyways thanks alot.

If thats the case you can disable SMB2.0 for the time being and later enable it once SEP is updated. http://blogs.technet.com/b/askperf/archive/2008/05/30/two-minute-drill-overview-of-smb-2-0.aspx