I have rebuilt the Tacac server for cisco secure ACS v3.0 and then retore all the data via the "data restore" under the system configuration.
After rebuilt, it was only working for one day... and then it fails to authenticate users. I checked the event viewer, the error message is:
ODBC authentication dll failed to initalise, code -1110
CSMon message: Problem Logging on to CSTacacs. Got as far as Starting Processing in Auth module