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RE: Stop User Account Control (UAC) screen flicker / flash

WAW8 — Mon, 24 Mar 2008 13:16:52 GMT

[quote][I would not recommend to disable the 'secure desktop' because it protects from the shatter attacks such as thewindow-messages passing between the processes[/quote]

You raise a valid point -- and I will modify the original post to mention the increased security exposure of doing this.

RE: Stop User Account Control (UAC) screen flicker / flash

nonfarlo — Mon, 24 Mar 2008 05:55:24 GMT

[quote][b]Jason (2/23/2007)[/b]

I hate that screen flicker. [/quote]

you have a problem with your graphics card driver, because on my Vista the screen does NOT flick and the UAC prompt is almost instantaneous, no flicker problems.

I would not recommend to disable the 'secure desktop' because it protects from the shatter attacks such as the window-messages passing between the processes

RE: Stop User Account Control (UAC) screen flicker / flash

Peter K — Thu, 06 Mar 2008 09:09:13 GMT

Here is the answer you need for the UAC problem:

[Moderator] Link removed.

Note: This topic is not about disabling UAC. This topic is about stopping the screen from darkening when UAC pops up. That is actually, believe it or not, a "feature" that MS calls Secure Desktop. It darkens because MS intentionally prevents you from doing anything else until you respond to the UAC prompt.

Disabling Secure Desktop doesn't disable UAC.

Disabling UAC does more than just stop popups, it also makes your machine vulnerable to the same kind of viruses and malware as back in the XP days. Not only that, it increases the risk of your machine hanging or seizing. How? Any not-written-specifically for-Vista application that needs to write to the registry or needs to write to Program Files, is going to need elevated rights to do that. By disabling UAC, you shut off the process to request those rights. The result is that these applications will fail silently, sometimes causing Vista to "hang" or seize in the process.

So, please don't post links to easy ways to disable UAC. We don't want to encourage this.

RE: Stop User Account Control (UAC) screen flicker / flash

WAW8 — Wed, 20 Feb 2008 11:53:34 GMT

No. This has to do with the screen darkening when the UAC popup appears. It has nothing to do with switching users.

Please post that as a new topic -- and don't post it here. This area is for people PROVIDING tips, not for technical questions. Please post that in the Technical Support forum.

thanks

RE: Stop User Account Control (UAC) screen flicker / flash

Michaelvg1 — Wed, 20 Feb 2008 10:22:20 GMT

Still confused. This flicker thing. When I switch users the monitor goes black long enough to where it wants to go into sleep mode, then switches to the other user sign-in. Why is this so slow? Is this what you guys are talking about? Can you fix this?

Thanks

RE: Stop User Account Control (UAC) screen flicker / flash

PurelyBarbed — Sun, 25 Mar 2007 22:28:41 GMT

nm, its under user accounts in the control pannle, i just turned it off, yay for me

RE: Stop User Account Control (UAC) screen flicker / flash

PurelyBarbed — Sun, 25 Mar 2007 21:53:02 GMT

no, im running home premium, its annoying as all get out!!

RE: Stop User Account Control (UAC) screen flicker / flash

Jason — Sat, 24 Mar 2007 14:57:14 GMT

[quote][b]PurelyBarbed (3/24/2007)[/b][hr]yeah i typed it in, and it can't find anything for secpol.msc what gives?[/quote]

Are you running Ultimate? I just tried it again on my system and it works.

i.e The screen flicker it is referring to is the darkened background which flashes when the UAC prompt comes up.

RE: Stop User Account Control (UAC) screen flicker / flash

PurelyBarbed — Sat, 24 Mar 2007 13:38:16 GMT

yeah i typed it in, and it can't find anything for secpol.msc what gives?

RE: Stop User Account Control (UAC) screen flicker / flash

Jason — Sat, 24 Mar 2007 13:12:19 GMT

[quote][b]PurelyBarbed (3/22/2007)[/b][hr]type it in the search bar?[/quote]

When you hit the start menu, there is a search bar at the bottom.

RE: Stop User Account Control (UAC) screen flicker / flash

jdonner — Fri, 23 Mar 2007 01:57:36 GMT

What screen flicker? I never get any.

RE: Stop User Account Control (UAC) screen flicker / flash

PurelyBarbed — Thu, 22 Mar 2007 22:52:56 GMT

type it in the search bar?

Stop User Account Control (UAC) screen flicker / flash

Jason — Fri, 23 Feb 2007 18:43:06 GMT

Stop User Account Control (UAC) screen flicker / flash

http://www.tweakvista.com/Article39105.aspx

Every time I get one of those UAC prompts asking me to authorize an administrative action my LCD screen flashes when the box pops up. This is caused by the switch to the secure desktop, similar towhathappens when you hit CTRL + ALT + DELETE. The only difference is that the background is a snapshot of your desktop that gives it the effect that it is just a pop up window.Although if you look carefully you will notice it is static since the clock does not change and anything else that was animated is now static.The secure desktopprovides an extra level of security to UAC by making it immuneto any application that may try to automate the click on the allow buttonbypassingthe purpose of UAC.

This sounds like a great thing but it is really annoying to me. I hate that screen flicker. Rather than disable UAC, there is a better alternative. Instead, I can just disable the secure desktop switch that causes the flicker. I know this is not as secure but it is better than disabling UAC completely.

Follow the steps below to disable UAC secure desktop:

Click on the Start Button and key in secpol.msc and hit Enter.
Navigate through Local Policies and Security Options.
Scroll to the bottom and right click on "User Account Control: Switch to the secure desktop when prompting for elevation" and select Properties.
Set the option to Disabled and hit OK.

[Update] It has been revealed that this does more than just stop the desktop from turning dark; instead, it turns off the Secure Desktop feature. Doing that exposes the PC to security risks as indicated below:

Normally, all processes running on Windows can talk to one another and interact with each other's interface. That's the basis of a lot of security exploits, which convince you to approve one action that in turn interacts with another process at your current level of privilege.

When you use UAC, the dimmed screen indicates that the consent prompt is running in an isolated process. No other software on the machine can interact with it. The only way you can give consent is to physically click the OK box, at which point control of the machine is returned to you.

When you turn off Secure Desktop, you enable scenarios where a program on your PC can in turn programmatically interact with UAC prompts without your knowledge. At that point, you're pwned.

So, be advised that you're exposing your machine to increased likelyhood of "shatter attacks" when you do this.