I am fixing a friends dell computer, he uses the DVI connector in a dual monitor setup. On the back of his Dell, the VGA port had a plastic tab over it. The monitor I use to repair PC's is an old VGA emachine model. I took the plastic tab off the VGA connector on the back of his PC, connected my VGA to it and get a "THIS MONITOR IS WORKING PLEASE CHECK THE VIDEO CABLE AND COMPUTER". I have never seen this before, is there a way around this, do I need to buy an adaptor, I am doing this for free so I don't want to spend too much. I have googled and couldn't come up with anything.

Thanks,
Steve J

Is the DVI cable still connected? You have have to use a utility of the PC to select which output is being used. Check under: Display Properties > Settings > Advanced

No, I took just the box from him. I cannot access anything since there is no display. I think I may have to buy a VGA to DVI adaptor. I have never come across this before, a plastic tab over the VGA slot, Dell, the evil empire.

I've seen it a lot on new computers I set up. You should have the DVI cable is usually provided in that case. The variable here is that it's a two monitor setup so you don't know what info is sent to what display.