“Failed to open database. Your license key is already in use”.

The most common reason this message can appear is if you have copied your data from one computer to another recently. It can also happen if the program wasn’t closed correctly.

Here’s what to do:

1. Close down the program.
2. Open the location of your database file (usually Documents > Book Collector )
3. Find the file that has the same name as the database, but with an extension ending in “lck”
4. It is called “YOURDATABASE.bkclck
5. Remove that file!
6. Now start up the program again, the warning message should no longer come up.

The other reason the warning can come up is if are trying to open the same database from more than one computer (concurrently) over a network using one and the same license key. This is not allowed, and you will in this case require additional licenses which you can purchase via our online shop.