You are going too fast. The BB reload needs time and rushing produces a corrupted OS as you found.
The link Ixxx8217;m adding will explain the 507 code but Ixxx8217;m suggesting you do a search for JL_cmdr on the forum site and follow the reload instructions for the OS. IT TAKES TIME!!
KB02792-Error message "507" appears on the BlackBerry smartphone while upgrading BlackBerry Device Software