we are using PIX 501. in the morning, when users are trying to connect to specific web site, they receive error 300. I have contacted the company that hosts web site, they said there is problem with firewall. I have check the "show run" in PIX and didn't see any unusual thing except "mtu outside 1500". does it cause the problem? how can I approach to troubleshoot this issue?
any suggestion would be very appreciated.