We have a Windows 2012 server that is a domain controller running as a VM on a 2012 host. All domain functions are working properly. DCdiag reports everything passed. All computers and other servers on the domain are working as expected. However on this server port port 80 and 443 http requests to any outside host fails.
If we ping (ICMP) any outside host from this server like yahoo.com or google.com we get a response. However internet explorer does not resolve any web sites we get "This page can't be displayed". The network icon on the system tray has a yellow exclamation point. We “can” connect via IE to any inside server on port 80 or any other port. When using telnet we can connect to any host server on port 80 inside of the network. We can telnet to a mail server on port 25 outside the network. However we cannot telnet to port 80 on any server outside the network. All other servers and PCs do not have this issue, just this one server. This just started happening for no apparent reason.
We have tried rebooting, resetting Internet explorer to defaults, clearing DNS cache, disabling SEP antivirus and firewall, verifying DNS on the server is working for all other PCs, have the DNS on this server pointing to itself and another working DNS server. We unchecked the “automatically detect proxy” in internet explorer options. The gateway is correct as it resolves all hosts at the command prompt. We disabled and re-enabled the virtual NIC from the host and the guest. We have managed switches but all are default settings so we have no ACL set up anywhere.
Any help will be appreciated!