I have a mobile telephone. I only ever switch it on every several months or so, because I hate them.

Today, I switched it on and it was completely dead.

I have a USB charger wire thing (IGo). I plugged it into a laptop (which has worked before) and it wouldn't work. I got one bar of power showing (no ascending bar pattern like when it's charging), and it still wouldn't boot up after about an hour. Another laptop at emgee towers manor doesn't ever work it. Said laptops are plugged into the mains at the time (the one today was on 'maximum performance' power setting as well).

However, I've just plugged it into my proper computer and it's charging like a good 'un. I could turn the telephone on after a few minutes.

 All are allegedly USB2 machines (the magic word 'enhanced' appears somewhere in the USB devices bit on device manager in all of them).  The laptops are Vista, the proper computer is XP SP3.

Why are these USB outputs different from each other? Is there a way to make the laptop ones work the charger?

If a phone has been standing idle for a length of time it can take 30 minutes or so for the battery indication to appear  in the same way as when the phone is new.

If you can advise me what make and model of phone you have I might be able to give you more specific advice.

I'd advise that you switch it on at least once a week to exercise the battery if nothing else.

If you are turning it on to check for messages it is unlikely they will have been stored for that long.