High Memory Utilisation since upgrade to OES11

Hi I have just upgrade a test server that only runs DHCP, DNS and DFSW but after two days mono just decides to use all evailable memory. If I restart apache it fixes the issue but is there anything I should look at. I am not even using mono on this server.

I do use iFolder but it is on another OES11 server which has also been upgraded and it doesn't have any issues.

Any ideas.

Thanks in advance.