UAC is really a guideline for home users, It provides a sense of security although it's not necessary for windows to function. I personally have it disabled because I know the things I install won't require permission to install. Also which version of Windows 7 are you using ? By version I mean Ultimate, Home Premium etcetera. You're also not using the latest version of Windowblinds . Latest version is Build 310.

If you think that you've fundamentally misunderstood what UAC does and what it is for. Disabling it is a huge backward step for Windows security and is not something I'll be doing. You can boast to me all you like how you never got a virus etc, I know people that drive around without a seatbelt who have never been injured, doesn't mean it's a good idea.

Thanks for that, I always installed through Impulse which says I have the latest version. I guess now Stardock sold it to Gamestop it cannot be relied upon so much. I'll go find the latest version and report back!

Version 7.30.047 should be the one available in the store. It shows as build 310 in About WB for me. This version works great so far.

 The version with issues is 7.30.037 Build 309

Do NOT use Impulse, it hasn't been updated yet.

A computer isn't really going to harm you as driving would but I was merely mentioning it. I use very good security software so UAC really isn't necessary as the acronym actually stands for User Account Control. Doesn't really provide much purpose but anyway. Back on topic

https://store.stardock.com/login.aspx?ReturnUrl=/myaccount/products

You can download the latest version from here.

Well I'm not going to get into an argument here but you are absolutely wrong on so many levels with this, UAC is designed as a mechanism to move Windows away from running administrator accounts all the time, the single biggest reason why Windows XP got so many crippling malware infections. There is no way I am risking my system by disabling it.

Ok, thanks guys I got the latest version and the problem still persists, every time a UAC prompt tries to appear I get "File system error (65535)" until I disable the Windowblinds skin.

It's Windows 7 Professional x64 by the way.

Absolutely anything that requires elevation via UAC, for example, right clicking on anything and choosing "Run as administrator". It's as if something is cancelling the elevation process as I hear part of the usual "beep" sound and the screen dim for just a split second before the error that appears.

 I found multiple hits on this error on Google. Most had the same fix. Try this:

1.    Open an elevated command prompt. To do this, click Start, clickAll Programs, click Accessories, right-click Command Prompt, and then click Run as administrator. If you are prompted for an administrator password or for a confirmation, type the password, or clickAllow.

2.    Type the following command, and then press ENTER:

sfc /scannow

The sfc /scannow command scans all protected system files and replaces incorrect versions with correct Microsoft versions.

This error has been reported here before. https://forums.stardock.com/402227

Unfortunately, the OP never posted if it was fixed.. Did you try running sfc in safe mode? Try what Neil suggests in the thread and report back, please.

I had suggested safe mode too. It's always recommended to do things like this in safe mode.

That is correct. UAC has extremely wide ranging effects.

The sfc /scannow in safe mode is one good idea. Another (though time consuming) is chkdsk /f /r  (also from the elevated cmd prompt).

I also recommend opening the support ticket ( support@stardock.com ). Wait for an actual person to answer. Mailing again only bumps the original request to the end of the queue.

This maybe so but I've yet to experience problems so far with Windows 7 and I've had it disabled since I installed in 2009. I was just expressing my opinion, No on really has to pay attention. If he feels safer using it then there is no harm done. 

Everyone's situation with a computer is going to be different. 

I have only one account on the computer, don' have UAC turned on and have the needed security software.  I run my updates, scans, defrag and back up once a week.  I am also of the age that I don't surf the net 'looking for interesting sites', just saying.  It doesn't mean that something can't make it's way on to the computer, at some point in time every computer picks up some unwanted items. 

The difference being without UAC you are trusting every application you run on your PC to be 100% safe, with UAC you can pick and choose, though of course if you go ahead and click "Yes" for everything you'll still get "pwned" as they say.

Yep, my system is completely patched up, latest Nvidia drivers and latest DirectX, I tried several of the stock skins and the problem persists.