I replaced the screen on my Toshiba C655-S5132,the laptop was plugged in at the time and now it will not power up. When I plug in the power adapter it says it charging but when I go to push the power button on nothing happens. Could the power cord have gone bad or what else can you suggest!

Hi basia1023 and Welcome to the new Techie7 forums.

Power cords don't normally go bad, unless the dog chews on it, or it gets yanked too hard. I fear there was a short or some other damage done to the charging/regulator circuits while working on live electronics (never a good idea unless absolutely necessary). If you meant the power supply (and not just cord) then that might be it - but you tried with just the battery and it still does not work - so that suggests something internal.

It is time to take it to a shop.