All email send to domain with mx records *-nl.mail.eo.outlook.com get stuck in the que with error 451 4.4.0 DNS query failed.
When i do a mx lookup to these domains i get a time out.
if i do a lookup to these domains to another lokal dns server i get no time out
If i do a lookup to these domains from a workstation i don’t get a time out but it takes about 10 seconds before i get an answer.
When i do i lookup to other domains i get no time out.
The problem begins last week. Before that everythings works fine.
We are working with SBS 2011 en exchange 2010 sp3. All email goes via edge server in DMZ.
Have anyone ideas?