internet explorer slow problem

I been having a problem with ie 6 becoming extremely slow. 2 days ago I was checking my active file list and came across two files in my windows application file that were not there 10 days ago. the files are Qxhjljkr and mmttil. Both of these had a cookie file and temp internet
file with same name extension which i found by doing a file and folder search. I delete all the found info and my problem went away....

question is does anyone know where they might have come from ? I do understand that I have not given you much to go on.
I also checked my download folder but it shows no downloads for over thirty days. Does anyone know how they were able to install something into my applications folder without downloading it?

 

I ran both spybot and adware before i did my manual poking around. They did not find anything, It seems the lastest problems I've had I've always found a cookie associated with it. Is this becoming the norm and does this method fool the protection systems ?

 

i ran hijacker and put a list in spyware specific