SD card not reading on laptop#1 but does read on laptop#2?

Hi.
My friend wanted to get photos from my SD camera card onto his Acer laptop via the card reader. He runs Windows XP. The card would not register.
The funny thing is that he could get some SD cards to work but some did not work on his laptop.

I was full sure it would resister on my Ubuntu 9.04 Acer laptop at home -> it did.

Does anyone know why this is? Is it due to the actual SD card maker or the card reader? Or perhaps even the OS?

Is there a solution to force the card reader to read the SD card?

 

It could be an older reader in one

SDHC (High Capacity over 4GB) is newer, and will not be read in older readers :cool

 

My card is a Lexar 4GB SDHC Card. Thanks for the info.