Hi AngelDaae.

Have you tried to boot into Safe Mode ? If you don't know how, you do like this ........
When you turn on your computer and it's finish loading the BIOS settings
( the hardware ) and just before it's beginning to load the windows settings,
I think a message appear saying " starting windows " ( I've gor a permanent boot menu so this message don't appear ) you press F8 and a menu with a lot af options appear, use the down arrow to the menu " Safe Mode ", it takes a while but once in windows try to go to " ad - remove software " and see if this " Windows Search Assist " is still on the list and uninstall it again.
If this isn't the case you can boot from your XP CD ( do you use XP ) and do a Repair, which dosn't erase your windows settings, but just repair the windows files.
On MS Website you can find a describtion on how to do it. You can find the site 2 ways.
1)
support.microsoft.com/default.aspx?scid=fh;[LN];kbjump
and type 315341 in the search field
2)
the direct link .....
support.microsoft.com/default.aspx?scid=kb;en-us;315341&Product=winxp

( you have to put " http:// " infront of both Url 1 + 2. I can't write the whole url so it's posted right )

In the article you have to look a bit down the page under " METHOD 2 "

Hope this will help - if you have any problems just write

Good Luck
Sanne