IE7 - Favourites Problem

Recently when i click on a favourite in IE7, i will get the following message:

Problem with shortcut: The target “” of this Internet Shortcut is not valid. Go to the Internet Shortcut property sheet and make sure the target is correct.

The property sheet is no longer there. The only way to fix it is to re-visit the site and add to favourites again. This seems to happen on random favourites and at random periods. I can use a favourite, do something else, and when i go back and use that same favourite, its broken. Alternatively, i can browse no problem for a couple of days, then the problem will occur again, for no apparent reason.

Their seems no “trigger” or specific pattern. I have loads of favs arranged in folders etc, which all seem vunerable to the problem.

Up until today, i thought this was a problem with my home PC. However, the same is now happening on 2 PC`s at work. I have been “asked” to fix it.

I have searched google, but there seems no definitive answer.

All machines are running XP Home SP2 & IE7. Fully up to date.

Anyone any ideas?