Sonicwall APL31-0B9 Internet Access restricted
My step daughter has a Sonicwall APL31-0B9, that someone installed years ago, for her boss. They have Comcast as the ISP into the Sonicwall FW then into a managed switch for both the PCs (3) and 5 VoIP phones.
Recently, they have lost access to the internet. They thought it was their Comcast being the issue, so they had a technician come out and troubleshoot the issue.
He claims he isolated the problem to the Sonicwall APL31-0B9 FW. However, when he removed the FW, they lose VoIP phones and internet service returned. When he connects the FW back in they restore their VoIP phones service and immediately lose internet access.
Any ideas, how the FW would allow this to occur? I would expect that if the FW was the cause of the failure, they would lose both VoIP and internet.
I'm going out this Thursday to see if i can further troubleshoot and isolate the fault. From what I've read, if no one on site has the password or configuration settings, they will need to purchase a new firewall, is this correct also?