Win2003 R2 Ver:5.2.3790

The network users are getting hanged while applying the permissions in Win2003 R2 Ver5.2.3790. H/W is Dell Server 4GB RAM,Xeon Processor 2.66 GHz DualCore, HDD 900 GB(C:12GB,D:55GB, E:302GB,G:533GB). The Files are saved in E&G Drive.

Can any one give suggest for the issue.