Why does my computer tell me it cannot find server - while I am using the internet?

This problem has happened 4 times since August and each time I have to contact my IPS I am told there is nothing wrong with their side - it must be my Wireless connection - they then tell me it's not a problem with the modem - it must be Norton AntiVirus Security. I have had computer programmers in to slove this - and each time it seems to be a different cause. If anyone out there can advise me, I'd be really greatful, as this problem leaves me without my computer for up to 5 days, until I can get help.

Why does my computer tell me it cannot find server - while I am using the internet?free anti virus

First, you said IPS means ISP (Internet Service Provider), right? IPS originally means Intrusion Prevention System for computer network security. You said computer programmer solve the problem, you mean 'computer technician', right? Anyway, it is a little bit confused people when you use those terms.

Well, let see your problem seems to be connection between your computer and the router. Since you mention you are running wireless network, I assume you have correct wireless setting and you used to be able to browse any web page without problem. My suggestion is get a CAT5 cable (network cable) and directly connect between your router and your computer. If this solve your problem, that means your wireless setting has problem. It could be range problem or some misconfiguration, I cannot tell you how to setup this without the router vendor name (different vendor has different setting). You could go to the vendor web site and download the manual, they will show you how to do that.