Well guys it's solved now!
thanks to ~ elitecarders

For annyone ever doubted him, he actually helped me secure and learn me how to prevent a hack like that in the future!

htttp://www.true-carders.com/

did he do it for free or charge you?

Free :P

It's very rare (trust wise) that you find someone to do that for free so make him your friend imo!

:D

Edit: Be sure to post in your paid request that it's been taken care of otherwise you may receive now unwanted pm's ;).

I know :)

I got experience with this so I acted a bit rough and suspicious in the start with him. After a while I gave it a shot and he actually helped me out and taught me how to prevent and now It's fixed.

The hacker changed two templates; "FORUMHOME" & "FORUMDISPLAY"

The hacker also used one of the admin's account to do this, cuz u could see a change in the teamplate from that account. The guy that helped me told me that he is being infected or someone know the password to the admin account..

Well after changing FORUMHOME & FORUMDISPLAY back to normal, everything works fine.. The only problem is that every "Custom modification/configure" to the templates or added custom pages was deleted...

When your done adding the customizations back in, stop right then and make a backup of your style, you can export it ;).

Elitecarders,

Can you say if this was this an undisclosed vulnerability, a misconfiguration issue or just an admin password problem?

Well some say I should feel suspicious, because he is owner of a illegal activities forum.. (Hacking) He told me he do it mostly for his own security.

It's like letting someone else wear your swim trunks - and then having to put them back on.

I am learning how to secure better and soon learning hacking techiques. (for security purpose) and reverse exploits.