Whatever the cause of these mysterious phenomena, the loss of your mail shows the value of backup. It's a good thing to realize you can lose all information on the hard disk at all times, if you don't have a copy on another medium.
See the tragic story of a lost term paper in http://reviews.cnet.com/5208-6618-0.html?forumID=6&threadID=14615&start=0
as an added example.
For the trouble with IE, repost your question in the XP forum. There are much more visitors there.
The only possible link between your two problems seems malware on the machine (but that's doubtful, it could just as well be two totally unrelated problems). However, it wouldn't harm to run all 5 of programs of the Anti-Parasite Suite. I can't find it on this site at the moment, but you'll find it reproduced in http://tips.oncomputers.info/archives2003/0311/2003-nov-16.htm; use google to find the new location of cwshredder!).
Better run these checks before turning to the XP forum.
Kees
I opened my Outlook today and found that all my mail from February 17 to March 5th was missing. How does this happen? Can the mail somehow be retrieved? It was there yesterday. I am also having trouble clicking links. All I get at times is a blank internet explorer page. Other times I get a box that wants me to find something. It looks like the box you get when you want to save a file. I am using WinXP, on a HP 734n, AMD Athlon 2400, Microsoft Office 2000 and IE6

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