In some cases, it is possible to recover a MailStore Database file that has damage using the built-in Firebird database backup and recovery tool gfix.exe
The location of the gfix.exe tool varies based on the version of MailStore:
Firebird directory locations are:
64bit Operating System: C:\Program Files (x86)\deepinvent\MailStore Server\Firebird3_x64
32bit Operating System: C:\Program Files (x86)\deepinvent\MailStore Server\Firebird3_x86