I've noticed a number of posts with the following issue with the ZCM10 client login:

"Unable to log into the network because the login credentials or the server certifiacte is incorrect"

I had exactly the same issue and was frustrated trying to find a solution to the problem.
Our setup is:

ZCM10.2 on Win2003 server using AD as LDAP source.

Re-creating the user source did not resolve the problem for me. Eventually I just removed the ZCM10 server from the windows domain (make sure you have a local account to log on as when it comes back up) and put the server back into the windows domain again.

This instantly resolved my immediate problem. This post is for information only in the hope that it may assist someone else with the same problem, but it may not fit all.