I'm trying to document a work flow with a series of screen shots. At one point in the flow, a UAC prompt appears, and I'd like to grab a bitmap of it to make my storyboard complete. Because UAC prompts are on a virtual desktop (or something like that), the usual Alt+PrintScreen doesn't work. Any suggestions?
This method using the group policy editor should do the job:
1) Run gpedit.msc
2) Under Computer Configuration\Windows Settings\Security Settings\Local Policies\SecurityOptions:Change “User Account Control: Switch to the secure desktop when prompting for elevation” to disabled
Undo this change after the screenshot, because it makes the system less secure!
Change your UAC settings to disable the secure desktop, and then you can take the screenshot. In Windows 7, this is one of the options on the UAC slider, in Vista, I believe you need to configure the Security Policy.
Alternatively, run Windows in a VM and take a screenshot of that.
You can also remote desktop to the Windows 7 machine and run the screenshotter (or video capture) on the other machine. I've used this very successfully.
A step by step Guide
Step 1. Right click on the Program that you want to install and choose 'Run as administrator'.
Step 2. Now when the UAC Prompt appears, click on 'Change when these notifications appear'.
Step 3. Take the security Bar one-step down. Be sure to find that 'do not dim my desktop' is in the description. Now click on 'OK'.
Click on 'yes' when the UAC ask for permission.
Step 4. Now close all UAC Prompt dialog box. Again start from the beginning. You are now able to take a screenshot of the UAC Prompt dialog box with keyboard's print screen button or ms snipping tool.
Note that it will make your system less secure. So, make the security level as previous after the completion of your need.
Simple method: Use windows accessory SnippingTool from MS. It just works!
来源：https://stackoverflow.com/questions/4046940/how-to-screen-shot-a-uac-prompt