18:44:20 ERROR: [9-119-1-00000219] Unable to scan database '\\<ServerName>\g$\archive\User_a.nsf'
18:44:20 NSFDbOpen:
18:44:20 Invalid NSF version
This is due to the Lotus Notes Client on the Notes Migrator for Exchange server being lower that the version the archive is.
Upgrade the Notes Client on the NME server to a version higher than the Archive version.