"Class not registered" error

Whenever I try to open file folder in Vista, I get an error popup that says "Class not registered" with no other details.

I'm using a three year old Toshiba Satellite Laptop.

I can open programs, use google chrome, firefox, but can't open file folders, recycle bin, windows update, the start menu or my computer.

I have run a few registry fixers, attempted a restore point fix with Advanced SystemCare, all to no avail.

Also, Microsoft office seems to be re-installing every time I open it.

Is there any way to fix Class Not Registered error?

The problem indicates that the troublesome areas are not associated with the registry.
If the problem just began use a system restore to return to normal.
If that does not work, a repair install may do the trick.
http://www.vistax64.com/tutorials/88236-repair-install-vista.html?filter[11]=Performance Maintenance
http://www.vistax64.com/tutorials/76905-system-restore-how.html