My server is doing my head in....

Yesterday, everything was fine.... Today I had to reboot the server due to an Remote Desktop issue... after the reboot I couldnīt login with my account.

Not with the Agent and not in the ZCC. I can login with the Zenworks administrator account.

When I try to login on the server with the Agent I get:
"... Unable to log into the network because the login credentials or the server certificate is incorrect... "

When I try to login to the ZCC I get:
Login Error: com.novell.zenworks.datamodel.exceptions.Untrusted CertificateException: com.novell.zenworks.datamodel.exceptions.Untrusted CertificateException: javax.naming.CommunicationException: simple bind failed: [Root exception is PKIX path building failed: xception: unable to find valid certification path to requested target]

I can log into the ZCC with the ZenWorks administrator credentials

Anyone any ideaīs what happened here?