Multi monitor problem

I want to run my Toshiba laptop (XP - home) with 2 monitors. I can get the
same screen on both monitors with no problem but I am having trouble
creating a single desktop across them both.

I go into the settings *** of display options but I can't get monitor 2 to
attach. If I right-click and select attach it seems to do it and it ticks
the box to extend the desktop across both monitors but as soon as I press
apply the 2nd monitor goes back to the shaded colour and if I right click it
says it is no longer attached. The tick in the extend dektop box also
disappears.

I have 2 working entries in device manager for display adapters.

Any ideas what I can do?


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