First thing to check for is the size of the H2 database. If it is over 5G, then the database needs to be migrated to MariaDB, MySQL, or MSSQL.
The next item to check for is to see if the server has shut-down right before the issue started. This could be checked in the Event Log Viewer. Once there, look in the Windows Logs and then Application. Scroll through this to see if there are any Errors that would indicate a shutdown. Also, look at the QIE Launcher Logs to see if there is any indication of QIE not being properly shutdown.
To start a new H2 database, login to QIE and do an export of all configuration.
Stop QIE from the QIE Service Manager.
Then rename the H2 folder as h2.corrupt.
Go back to the QIE Service Manager and start QIE. This will create a new H2 database.
Lastly, import the configuration that was exported earlier in this process and the start channels.
