Adapter not working - Dell Laptop

I recently got a new adapter for my dell inspiron1420 laptop as the older one had stopped working. My friend is having troubles with his adapter (it's not charging) so I let him use mine.
After he gave it back, it seems that my adapter is no longer working. Nothing pops up, but when I press the battery icon it says "0% plugged in, not charging".

Is there something that will make an adapter break through a computer? The fact that my friend's adapter is broken and then my adapter broke after he used it, points to his computer being the one to blame. Maybe a virus? Can I fix this?

Your friends laptop probably has a shorted motherboard charging circuit that took out his AC adapter and your AC adapter... His laptop can be repaired, but the AC adapters will have to be replaced. Were these adapters Dell, or were they cheaper substitutes?

Yeah, it's a dell adapter. When I posted this thread, it wasn't working, but then I waited a couple of hours and it was working again. Then, a couple hours later, it wasn't working. Now it is.
Lol, I'm not sure if it's broken or not, but something is definitely wrong. I guess I'll just have to wait and see, but I hope I don't have to buy a new one. :(

If he has a shorted motherboard charging circuit (sorry, I don't know what that is) doesn't that mean the new adapter he will buy, will eventually break? That being if he doesn't get it repaired.