Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '' for key 2' in E:\xampp\htdocs\pot\OTS_Account.php:110 Stack trace: #0 E:\xampp\htdocs\pot\OTS_Account.php(110): PDO->query('INSERT INTO `ac...') #1 E:\xampp\htdocs\createaccount.php(258): OTS_Account->create(98765, 98765) #2 E:\xampp\htdocs\index.php(139): include('E:\xampp\htdocs...') #3 {main} thrown in E:\xampp\htdocs\pot\OTS_Account.php on line 110
how can i solve this problem? I had this when i was using the newest XAMPP, but now i'm using 1.6.5 and have this again ;< ...or similar...
I have compiled the newest TFS and when trying to login my server i have an error:

Maybe this is problem of my compilation?