When configurating or performing a maillevel backup, the following error can occur: logonSession ” ERROR= MAPI_E_CALL_FAILED Detail= Unspecified error” during a backup job. This problem is caused by the MAPI Files that are stored on the system, and the error can usually be found in the WIndows event log (as it is a WIndows related error). This is often caused by a previous used backup software.
To resolve the issue, please verify if the Mapisp32.exe file does exist on the system (C:\WINDOWS\system32\mapisp32.exe). In some cases, the Mapisp32.exe file may have been removed or renamed by anti-virus software. You can restore this by reinstalling the Microsoft Exchange Server MAPI Client and Collaboration Data Objects 1.2.1 (ExchangeMAPICdo.exe).
Make sure you uninstall the old version first. Then run Mapisp32.exe. Disable old back-up software (i.e. backup exec), and make sure outlook, outlook express or windows mail are not installed on the server.