After Disaster Recovery a lot of clients show offline status

Hello,

Recently I made a disaster recovery, everything its fine until one or two hours after the process, some clients show online but then they turned offline and never put online again. If I return to the last server all clients work fine

I'm workin in Windows 2008 server x64 R2 whit Enpoint protection manager 12.1.1000.157 RU1.

Thanks in advance for help