Hi. I have a unusual problem and would be grateful for any advice..

I have a 2860. Suddenly, no phone or broadband, but if I disconnect or turn the router off, I get a dial tone and can make phone calls. The second I power up or reconnect the router, I get no dial tone and my cordless handsets display a "check phone line" message.

I have an MK1 phone socket.

Thanks.
Sarah

You need to call your service provider , that is a line fault.