Loss of Outlook Express & Media Player 9

I keep losing the use of OE & MP9.
I can reload MP9 easily, but the next day it has probably gone
- may be Limewire??
Of greater concern is OE. (My son uses Hotmail, that is OK.)
I can sometimes restore it, but I have just done a full reboot to get it back, and lost it the next day.
I am running Me, and at the moment few Progs are set up.
I run AVG, Spybot & Adaware, none of which are yet set up.
Any possible conflicts??

 

wait... do they just stop working or something? More details please, system specs, etc...

 

The shortcut icons, and the programs just don't respond, no messages.
The icons then go to "blank screens".
Very few programs running as I have just rebooted, AVG ,Adaware, Spybot not yet set up.
C/A/D reveals Capswiz, Msnmgr, Loadqm,Wjview, and one I thought I had got rid of - 70000041.
Any thoughts?

 

boot in safe mode and delete the 70000041.exe file
It's a trojan downloader.

 

Loss of OE6 & MP9

Still losing OE6 & MP9.
No sign of 70000041, nothing obviously nasty in HijackThis.
Is no one else having this problem??