Urgent - Problem( Sites not open on my server....)

Hello,

i’m installed avast! 4 Server Edition on my server today, but all my sites hosted on my server down now and error: HTTP 500 Internal server error.

( notes: my iis running/all sites running/internet connection okey/i can open Cpanel and Webmail ( example: site.com:8077 for panel and site.com:8383 for webmail) and send/receive email working )

Please tell me how i can fix this problem.

Thanks

What if you stop the “avast! antivirus” service (Administrative Tools → Services). Does the problem disappear?

Thanks
Vlk