UCS 4.2 Errors when running diagnostics




preparing our Update to 4.3.1 in 2 weeks i have run the diagnostics tool and get some erros which i want to fix during (or before) running the update.

We get the following critical error from the diagnostics:

The following KDCs were unreachable: tcp cgn-dc2.company.intern:88, tcp dc.company.intern:88, tcp dc2.company.intern:88, tcp cgn-dc1.company.intern:88, udp cgn-dc1.company.intern:88, udp dc2.company.intern:88, udp dc.company.intern:88, udp cgn-dc2.company.intern:88
No reachable KDCs were found.

Anyone knows how to solve this or what exactly causes this error?

Best regards