Has anyone else had this problem.

I bought a 4gb Integra micro sd card and was able to transfer information from my computer onto the micro sd card (through a T-Flash card reader) with no problem.
Now however the computer doesn't recognise it.

I have bought a new Mikomi carder reader and new 1gb Kingston card just in case either was faulty and still the computer doesn't recognise any combination of them.

With the Mikomi card reader the computer assigns a drive letter, but says the card needs formatted. When I try and format the card, it says there is no disc in the drive.

My system is Windows XP Professional, Operating system Version 5.1.2600.

I have looked in Device Manager and everything seems to be enabled, but dont really know enough about systems to be messing around with them.

I have turned the computer off, unpluged and then started up again with no effect.

Is this something that can be fixed, and if so any recommendations of who to fix it.