If your Exchange information store will not start, or stops responding, and you receive:
Event ID: 145
Description: MSExchangeIS ((%pid%) ) The database engine could not access the file called %database path%\edb.log.
where the file listed may be any file in the database directory, then some program/process has the file locked.
To determine if it is really locked:
copy <database path>\edb.log %TEMP%
If you are greeted with:
The process cannot access the file because it is being used by another process.
then the file is locked.
Common causes are ant-virus or backup software. Configure these to ignore the
Exchsrvr\Mdbdata or Exchsrvr\Dsadata directories.