After updating from Pro 3.02 to 3.03, I got many errors 500 and the website wasn’t able to run correctly.
We found that the trouble comes from the statistics add-on.
After uninstalling this add-on, everything works fine and all errors 500 have disapeared.
Does anyone had the same trouble ? Or any idea what’s going wrong ?
Have you tried re installing the addon, maybe it will re load OK
John
Mmh I tried to re-install the add-on.
It actually seems to work.
Will see in the following days if it goes wrong again but your advice seems to be good 
And so easy ^^
Thanks.
Odd, usually a 500 error is more related to Apache config than to the site (generally). Are you getting the “Server missconfiguration” error or some other error describing the 500 error code (general for service not available).
After enabling the statistics add-on again, it works well for about 1 days and then crash again.
I disabled the add-on and again it's fully working well…
There's really something in this add-on that cause the error 500 on our server 
#tbirnseth, sometime, the page does not load fully, sometime here's the message that show :
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator, webmaster@400coups.ch and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.
Check directory permissions. If you're running suPHP, change the mode of ALL directories to either 755 or 750 (preferred). If it finds a 777 it will generate the 500 error.
Thanks tbirnseth. I had two rep (cache and logs) that were on 777.
After placing them to 755, everything is working fine for 2 days now.
It seems just a little bit slower to access pages now but everything is working.