Traceback (most recent call last):
File "C:\Program Files (x86)\Bethesda Softworks\Morrowind\Mopy\masher.py", line 2091, in OnSave
fileRefs.safeSave()
File "C:\Program Files (x86)\Bethesda Softworks\Morrowind\Mopy\mosh.py", line 4799, in safeSave
renameFile(tempPath,filePath)
File "C:\Program Files (x86)\Bethesda Softworks\Morrowind\Mopy\mosh.py", line 546, in renameFile
os.remove(newPath)
WindowsError: [Error 13] Access is denied: 'C:\\Program Files (x86)\\Bethesda Softworks\\Morrowind\\Saves\\Drizzt0000.ess'


This is a new one. Mash hasn't ever given me trouble.
I just reactivated the UAC on Vista, if that may indeed be the culprit.

I've seen this a few times. They tended to have been caused by a mod, though the error message always mentioned the name.
Try disabling UAC?

Voila!
Yet another reason to keep that thing turned off.
I was chattin with some tech guys the other night and they were telling me how UAC is an important feature and how I should have it on and how it kept one guy from getting a virus.
I very begrudgingly decided to turn it back on.
But now it's off again.
I've never had any problems anyway.
Sorry to waste thread space. :facepalm:

Ha.. never use UAC unless you want to be riddled by pointless "DID YOU START THIS APPLICATION?!" popus and/or you're not good with computers.

The UAC is only good for people who know absolutely nothing about computers. For anyone who knows something about computers, its much more of a hassle to keep it on and tends to inhibit much more then help. Having proper security programs and using common sense will stop you from getting most viruses.
Aside from that, I had trouble once with a mod stopping me from cleaning a save, I got rid of that mod.

Yaay!! another person to give the link to for changing security settings on files. With the instructions on the below link you don't need to disable UAC and anyways disabling UAC won't remove all problems and changing security settings on files and folders will.

http://www.blogsdna.com/2159/how-to-take-ownership-grant-permissions-to-access-files-folder-in-windows-7.htm

Follow the instructions on your Morrowind folder and you shouldn't have any more problems.

I have Vista.

Works the same way with Vista also.