My server and client were working fine until i updated the client just to add avatars and pets, but here comes the **** part

; i restarted the server and run the loader, i pressed the start button on the loader and the game was flashing black screen

..so i decided to rollback what i had done; i replaced the server files, restored a new database, deleted the client and replaced it with new one but the same **** happened

......
I have been struggling to find solutions for two weeks, searching threads in all forums but nothing is found as if i am the only one whom this **** happened to him....please any helping hand is needed, i will be grateful