Xp Will Not Load

[axus]

I have a laptop running on XP. When we switch the laptop on, it displays a message "System presence detect unavailable, startup halted" or words to that effect. It then seizes up and I have to turn it off.
It was OK when it was turned off the previous night. Any help at "dummy" level would be appreciated.
Thanks
Keith

[Lowland]

Be useful to have the EXACT error message

Can you start it in safe mode?

[NooNoo]

Welcome to Windrivers Axus.

Have you recently updated this laptop?
What point exactly does it freeze - do you get to the windows loading bit?