Windows Vista Laptop dwmredir.dll error on login

A staff member brought their laptop in. Upon booting it up it auto logs in but before it can load the desktop or anything it comes up with the error:


"C:\Windows\system32\dwmredir.dll is either not designed to run on Windows or it contains an error. Try installing the program again using the original installation media or contact your system administrator or the software vendor for support.


Found this microsoft tech forum which suggests:

1. restore to just before this happened - unfortunately there is no restore points!!
2. try a clean boot
1. goto -> run -> msconfig
2. disable startups
3. disable non microsoft startups
4. try and rule out which one is causing it
3. tryed these to no avail. Still no desktop

Found this forum which says to run some error checking thing called "System File Checker". From command line type:

sfc /scannow

............

I've just found this post under "drafts". Looks like I didn't finish the post. From what I remember, I think I booted in Safe Mode, turned on the installation service (see previous post), installed Tune Up Utilities and ran "One Stop Maintenance". I think this is how I fixed it.


Simple.