Common error codes:
1 - Unable to open database 2 - Database corrupted 3 - License checksum failure 4 - License limit exceeded 5 - License limit exceeded 6 - Product not licensed 7 - Unknown license failure 8 - License DB too large 9 - Heap error 10 - Cannot contact License manager 11 - Message send failure 12 - Message receive failure 13 - Returned checksum failure 14 - Integrity check failure 15 - License limit exceeded - no overdraft 16 - License limit exceeded 17 - License limit exceeded 98 - User tampering with license system 100 - User tampering with license system