Symptoms

Adding more than 10 databases to Plesk under Web Admin Edition license fails with error:

Warning: There are no available resources of this type (MySQL databases) left. Requested: 1; available: 0.

Cause

This issue has been considered as software issue #PPPM-4923 and will be fixed in future product updates.

Workaround

Set Unlimited value in psa database manually:

# plesk db
UPDATE Limits l SET value='-1' WHERE limit_name='max_db'