[Important!] Attention users of the merge system version 1.6.1 and earlier.
If you’ve used the MyBB Merge System v1.6.1 or earlier please download the file attached here, upload it to your forum root, and run it by going to http://yourdomain.com/yourforumpath/icr.php for security purposes. The reason for this is a potential security breach related to the “old db” password being stored in the datacache in plaintext form. [...]