@TimRice has the answer, but here are some related posts that go into some extra details:
Related Posts:
- Odd BESClient behavior on laptops
- Windows Firewall preventing UDP
- Stubborn Clients
- Open UDP 52311 confirmation?
- Forced Reboots via BigFix
Related content:
- http://bigfix.me/relevance/details/29990871
- http://bigfix.me/relevance/details/2996925
- http://bigfix.me/fixlet/details/37981
- http://bigfix.me/analysis/details/2994765
- http://bigfix.me/analysis/details/2994616