I have this previous problem
http://forums.iis.net/t/1207540.aspx?Scheduled+500+Internal+Server+Error
And today, the error came back. Strange thing is that, the connection to the website is fluctuating, some viewing tries succeed, some tries got the internal server error.
Tried to restart the Default website from the IIS and the website works fine.
Please could someone help me. I suspect I am missing some setting in the IIS and folder permissions