Issue: Intermittently I am unable to access NAS shares from amy 2008 R2 Server or my Win 7 machine. If I restart the workstation service or reboot the server we are able resolve the issue. I have SEP 11.0.7000. Please don't say that SEP is the cause. I removed SEP still we have the same issue. I update the NIC drivers still unable to fix the issue. Please Help.

What is the vesrion of Mrxsmb10.sys ?

Please apply the hotfix http://support.microsoft.com/kb/2194664 You cannot access a remote server that shares files and printers by using the SMB protocol from a computer that is running Windows Server 2008 R2 or Windows 7

Along with that we need to update mrxsmb.sys Apply the hotfix in sequence 2194664: You cannot access a remote server that shares files and printers by using the SMB protocol from a computer that is running Windows Server 2008 R2 or Windows 7 2612966: Paged pool memory leak when you access some shared files in Windows 7 or in Windows Server 2008 R2 2563210 : SMB connection is reset if you cancel a file operation over a network connection in Windows 7 or in Windows Server 2008 R2