The following error may be seen in the logs for the Archive Manager Exchange Store Manager (ESM) service or the Archive Manager Data Loader (DL) service:
ERROR: MIMEHeaderParser.CreateInstance:
16:21:07 [80040154] Class not registered
16:21:07 Statistics for this run
The Dell.AM.ESM.Mlib.dll is not registered.
To register this DLL, click Start > Run and type in:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe “C:\Program Files (x86)\Dell\Archive Manager\Dell.AM.ESM.Mlib.dll”
Restart the ESM and the DL service once complete.
Also see: https://support.quest.com/archive-manager/kb/85260