Attempt to move a non-existent user database raises exception

[delphidabbler]

It would be best if the Backup User Database & Move User Database menu options were disabled when there is no user database. Although backups work OK - they just create an empty backup file - it is a bit pointless.

[delphidabbler]

Additionally, although they don't raise exceptions the Database | Backup User Database and new-for-next-version Database | Delete User Database really should be disabled when there is no user database to operate on.

The former simply creates an empty backup that Database | Restore User Database will happily restore, but this really makes no sense.