On the Cisco CallManager 4.x, whenever MLA is turned on, access to the Publisher Server fails, and the login screen comes back up and asks for the username and password. But, access to Subscriber Server is fine with the same credentials.
In order to resolve this issue, complete these steps:
Run Adminutility in order to check the password synchronization for SQLSvc, CCMServiceRW, CCMService, CCMCDR and CCMUser in the Cisco CallManager cluster.
Check registry settings as indicated in Cisco bug ID CSCeg00750, and make sure they are same on both Publisher & Subscriber.
This issue also occurs when SQLSvc password is not sync with MLA and system. In order to correct this, look for synchpwd.dll in the c:\winnt\system32\synchpwd.dll . If this DLL is there, then the publisher uses this file instead of the c:\program files\cisco\bin\synchpwd.dll. Hence, the password in the publisher is never in sync with the Subscriber.
Remove this file from c:\winnt\system32\synchpwd.dll and then copy the synchpwd.dll file from the Subscriber to Publisher. This is the file that it uses to sychronize the password with the Subscriber. Reset the password again or otherwise the same error shows up again.
You can check the synchpwd.log in the MLA trace folder in order to see if the new phrase password is set.
Refer to these articles for more information about MLA Login failed issues: