I am in urgent need of some assistance. My client has a windows SBS2003 server running Exchange 2003. We use a sonicwall Pro for router/firewall/vpn. My client's office had renovations done to it during June and July and I hosted the server and sonicwall on my Verizon FIOS. For two months, it worked perfectly without any problems. I have recently brought back the server and sonicwall to the client office location and connected everything back the way it was and modified the settings on the sonicwall for their Verizon FIOS.
Everything will work perfectly for about 5 hours. Server, Internet, Incoming and outgoing emails are perfect. But it seems like every 5 hours, the Internet goes down which prevents me from supporting the network remotely. All PCs and server lose access to the internet so emails stop working as well. A simple reboot of the sonicwall restores everything perfectly, but only for another 5 hours, but then it goes down again. I am going nuts trying to figure this out. I don't think it is the server because rebooting the sonicwall gets everything back up so I am under the impression that this is sonicwall, or FIOS related.
I have checked all my settings so many times. DNS, Firewall, DHCP, it all looks good. What could cause it to work for 5 hours and then cause an internet outage?