Doubleclicking in a folder won't open it (just happened)

Hi.

Im new to this forum, so please feel free to comment on anything in my post.

As stated in my title, a new problem has occured today. To clarify what could be the problem, I will write what I have done today, with my pc.

I just started working with setting up mail client on my NAS server, and was working with portforwarding of my router.

At the same time, I updated my windows 7 (autoupdate) and after a reboot, the problem occured.
I can boubleclick on folders on my desktop, but when I enter the "folder surfing" (old pathfinder) I can't doubleclick, I get the following error

(in Danish)
"Denne fil har ikke tilknyttet program, der kan udføre handlingen. Installer et program, eller hvis et program allerede er installeret, skal du oprette en tilknytning i Standardprogrammer i Kontrolpanel"

(translated by me to english)
"This file has no program associated with it that can perform the action. Install a program, or if a program is already installed, you must create an association in Default Programs in Controlpanel"

I have been to the Controlpanel to look at the options, but nowhere could I find the option to change the program needed for doubleclicking on folders.
All other files still react normally when I doubleclick on the files - only folders are the problem.

"Rightclick -> open" still works, so I am able to open the folders, but not by doubleclicking, which is realy annoying.

Any help would be apriciated.


I have a MSI laptop with Windows 7 Home Premium (32bit)
Intel Core Duo P8400
4GB ram

One option would be, after restoring, just install the updates one at a time and check and see if everything works between each one. That process of elimination should help you discover which one is the problem.