If you look at the release notes of the current releases there is at least one problem fixed about Win2k8R2 domain controllers and clients unable to access  Without a service request that looks at a network trace it’s hard to diagnose There are quite some changes in AD implemented in Win2k8R2  In these day and age of software getting updated rapidly it’s not a good idea to go 3+ years without an OS upgrade If you would do that on your Windows systems they would probably in much worse shape and being infected with viruses and trojans
So I recently added a new Windows Server 2008 R2 server to my existing network of 2 2008 NON-R2 servers (both acting as DCs). This new server has been tasked to be a DC, run AD & DNS. After getting AD & DNS set up successfully, the only problem I have now is that users connecting to our NX4/Clariion CIFS file shares receive an Access is Denied message. Even after typing in good Windows credentials, they get a popup similar to this: [IMAGE] I find it strange because DNS is clearly working (they are able to ping by internal file name) and also my users can cannot to other file shares (regular ol' windows shares, non-EMC) in our network. Everything was working fine before I added this new server too.  I think the only difference with this new server is that it is running Server 2008 R2 compared to the other DCs. I'm wondering if there is some sort of trust relationship between this new server and the SAN unit that I have forgotten to establish. Any ideas?
Added a new DC, and now users cannot connect to my existing CIFS