why does archive manager open when home folder is clicked

On ubuntu 10.10 when i click places and try to open home folder, the archive manager opens this also happens with all the other folders until you reach computer. when you click computer you can access all the other folders from the left hand side menu. i don't know why this is happening nor can i find any reference to it happening to others. i have had a 10.10 beta on my machine before, and it drove me to distraction and i switched back to 10.04 which i will do again if necessary.