Plugged in ... Not charging??? why???

In november my battery was not charging. I talked to Dell Support and they said my battery was dead and I needed a new one. Then after a day or so it started working normally again. BUT by then I ordered a new battery from net also Dell accidently came with a replacement and took my old one.
So I ended up with 2 new batteries!

Anyway the charging started to work again normally.

Now nearly 2 months down the line the same problem is back. both batteries will not charge.

Battery charging light on front of laptop comes on for about 5mins then goes off.
Maybe it is a problem with the AC Charging unit. Not sure but the light comes on the AC Adapter and I can run the Laptop when plugged in.

When my XPS M1330 started overheating after the first motherboard replacement, I got the same problem.

I plugged in my friend's AC adapter and it was charging the laptop just fine. So I contacted customer support and they have replaced me with the new AC adapter.

same prob here. i thought is was the ac power adapter cord since i had troubles with it to begin with. now my battery isn't recognized -the battery is only 4 mo old

i'll have to buy a new dell adapter, new laptop or what they really want me to buy---the extended warranty. since my warranty just ran out dell wants me to pay for a new adapter. but i mean it was their fault to begin with