[dhughes0941]

I have attempted to use an PS2 to USB adapter for a mouse on my HP Laptop running Vista. Vista cannot see the mouse via the adapter, the adapter is simply a piece of hardware, no drivers are necessary?? What must I do to make it work? thx.

[TheOutcaste]

Welcome to TSG!
Is your Mouse a PS/2 and USB mouse, or a PS/2 only mouse? The adapters only work if the mouse is capable of being used on both interfaces.

[dhughes0941]

It is a PS2 originally I purchased an adapter to convert to a USB port using Vista.

[TheOutcaste]

The real question is, is it PS/2 only.
Did the mouse come with a PS/2 to USB adapter? All the PS/2 mice I've seen that can work with both interfaces came with the adapter. If it didn't, it may only work on the one interface type. Some USB mice that work on both interfaces don't come with a USB to PS/2 adapter to save costs.
Only way to tell is to check the documentation or the manufacturer's web site.

Technical info for the curious:
PS/2 is a 4-wire interface (3 if you share the ground wire), with two signals, Clock and Data, referenced to the ground, aka single ended.
USB is a 2-wire interface, D+ and D-, using a single Data signal on a twisted pair. This is not referenced to ground, but is the difference between the two wires, aka a differential signal. There are also 2 wires for power, +5 V and ground.
The electronics inside the mouse have to know how to communicate with both the PS/2 and USB interface protocols for the adapter to work. It decides whether to use the two signal lines as a differential pair or as separate clock and data signals with the ground from the power.