New php scripts causing 500 error?

Lately whenever i upload a new script to the server i.e. invisionboard v1.3.1 final , phpbb whatever it causes 500 internal server errors...
I've tried setting ftp to upload in the right format instead of auto.. tried uploading in zip / .tar.gz and extracting on the server and all cause the same errors....
Vbulletin however seems to work fine.

I have php v4.4.0 and the respective Zen Optimizer installed using cpanel instalzendopt.

Everything used to be fine.. im not sure if it started after i upgraded php or not.. What causes the error on non-modified scripts straight from the developers? and how can i fix it?

Thnx.

 

 

 

 

Top