I have seen this error in many Zimbra installations but I'm going to talk only about the current scenario: I'm running Zimbra OCS 6 in RHEL 5 and the console admin gives me error on all services.
However all services are running fine according to the probes I can do (send/receive email, authenticate, antispam/antivirus, etc) and according to:
$ zmcontrol status
... that says everything is running.
The attached image to this post shows the error I'm talking about.
Sometimes I just login again to the console admin later (hours or days later) and this error isn't shown anymore.
Do you know why this could happen? I hope someone can help me.