The database files can not just be simply removed.

If IME is still functioning, then you can do the following:

Select Tools->Preferences

Modify the "Maximum number of events in current event file", and the "Maximum number of archived files".

The maximum number of events will reduce the largest size that each event file can become.

The maximum number of archived files will reduce the total number of database files that will be saved.

You may also want to "Enable time schedule for archiving events", and temporarilly set it to every 10 minutes.

Then keep an eye on the alarmDB directory over the next hour or 2.

Continue to change the settings until you are comfortable with the amount of disk space it will be using.

You may also want to change the archive internal to once a day in order to prevent a lot of small 10 minute files in the future.

If you need to save old alarm information, then you may want to first export the old alarm data before making the changes above.

Select the File->Export option and select the time frame you want exported and browse to a directory on another disk where you want the file created.