If you are using the Volume Shadow Copy Service (VSS) software provider on a system running Windows 7 – Service Pack 1, Windows Server 2008 R2 – Service Pack 1 or Small Business Server 2011 – Service Pack 1 then you may find the computer randomly stops responding.
This occurs because volsnap.sys tries to obtain a lock again on a file even if it is already holding a lock.
A hotfix can be requested to resolve the issue using KB 2627052 http://support.microsoft.com/kb/2627052
You may find that Login Scripts are very slow to run when you are using any of the following operating systems:
Windows Vista – SP2, Windows Server 2008 – SP2, SBS 2008 – SP2, Windows 7 – SP1, Windows Server 2008 R2 – SP1 or SBS 2011 – SP1
The boxing feature causes the login script to run at a reduced priority for the first 60 seconds, a hotfix is available from Microsoft that improves the speed at which the Login Script runs. This can be found in the Microsoft knowledgebase under KB 2581608 http://support.microsoft.com/kb/2581608