Our cable broadband works fine on our other computers (through our router). However, on this computer (HP laptop running XP Pro - and my daughter's laptop (also HP on XP)) whenever returning to the computer after a period of 5 or 10 minutes, after opening Internet Explorer (or if I left it open), a message pops up saying the internet is not connected, and asking if I wanted to 'work offline' or 'try again' to connect. It's connected via wireless, and this problem happens on both my laptop and my daughters.

Any suggestions on how to get rid of it?

Thanks,

Andrew