pc to screen using vga not working

[daiemus]

I reformat my pc with win 8 using my Tv as a screen.Afterwards i tried plugging my pc screen back in and it says no signal...Please Help ASAP

 

[hang-the-9]

Did you shut down the PC, connect the screen and turn on the PC or just swap cables to the monitor?

Did you make sure the resolution you set the TV for is compatible with the monitor?

Check the cable at both ends make sure it's not loose.