Error 500, nothing on Logs

Hello,

I'm running an PHP forum application.

On a specific page I just get an error 500.

The PHP error log is enabled but there's no error about that page. There are other errors (i have disabled notices & strict)...but nothing on that page.

I have also enabled FailedRequestTracing, but it gives me no valuable information...just error 500 on fastCGI module.

I cannot track down the error.

Any ideas?

Thanks

A.