Transfer/Copy Account -> Internal Server Error

[Bakadesu]

I just transfered/copy an account from another server with WHM. But when I try to go to the server IP, it gives me 500 Internal Server Error, however, the account that I transfered works ( http://xxx.xxx.xxx.xxx/~username ). Everything else seems to be okay. The server IP was working fine until I transfered the account.

I already tried restarting apache, cpanel, bind, /scripts/upcp --force
I can't think of anything else.
Any suggestions?

*** EDIT **

okay, I checked the error_log also.

I got "Premature end of script headers: index.php"
and some:
"File does not exist: 500.shtml"
"File does not exist: 400.shtml"
"File does not exist: favicon.ico"

How do I correct this? I never got this error when I access via http://xxx.xxx.xxx.xxx/~username