error 500 details

[alexgg]

My site (mediawiki backed) often returns error 500 page (and it mentions that requested page is not found also). Does anyone know how to make this page reveal some more details or where is the error log? Error log from cPanel is empty.

 

I believe it is a result of no activity on site for long time. Because it happens only after long inactivity time and I am receiving error 500 only for few first minutes. And then everything work fine.