I think I got my Acer one 2 years ago and now the battery keeps having a problem along with the charger (I have to keep messing with it until it's in the right place and starts charging) and then it's annoying because I usually get the blame for it like I messed it up but the 3 last laptops I've had in the past 5-7 years have been $300-$400 only...so how long should one usually last?

Generally ill buy a new one every year. But they should last 2-4.

Added after 3 minutes:

Honestly stop paying 300-400 for a notebook and drop a grand or two. My MBP is still doing great. If you like Windows though go with Lenovo, you can throw them down stairs and they will be fine.

They should be lasting atleast 3/4 years unless you're being pretty darn rough with them.

I bought my HP almost 2 years ago and I've started to notice it slowing down, but it's still good. I dropped a good $750 on it though. Like Danger said, don't be afraid to spend more on it because you generally are paying for quality.

So it's either the AC jack itself that has a bad connection inside the laptop, the AC adapter has a loose jack (if it's one of the two piece type AC adapters), or a short in the AC cable.

Whatever the case, none of those parts should have a "shelf life". I guess it comes down to how much wear and tear you're causing it and how cheaply it's built. I can't speak on how you take care of your stuff, but I can tell ya that Acer's consumer brand stuff sure isn't built the way it used to be. Either way, it sounds like you need to be gentler with your stuff or buy better stuff.

I have an HP Laptop since 2007 and it's working perfectly except the battery.

I had an asus netbook, I bought it in July 2009 and then the keyboard stopped working in April 2011 because I accidently spilled some liquid over it. Well it was my mistake. But they usually live for more than 2 years..

Yeah as long as you don't spill or drop it or get a deadly virus they usually last for like 3 years.

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Hehe, lenovos are spill proof. The keyboard traps and sends the liquid through holes in the bottom of the machine, keeping the innards safe!

Well it depends on a variety of factors. These factors can range from the number of times you dropped it, to amount of porn watched, to the amount of time being on, and being plugged in, to how much you eat around it.

Some may affect your comp more than others, a crumb in the keyboard could be less deadly then being dropped 3 feet obviously.

My laptops last about 3 years.