No domain availible to validate password

I have a dial up connection set up at home to access my work email, and network drives. When I dial in and log on, I get the error, no domain avi to validate password…I click ok and I’m logged on. I can access my email just fine, but I can not browse the network. I get an error there too. I have the correct workgroup set up, the correct domains etc. I have double checked everything. I even checked the set up of another home pc and I changed my settings to match. Still getting an error