Solution to Error: Alt + F4 and Ctrl + F4 won't work - Windows 7

Alt + F4 and Ctrl + F4 won't work - Windows 7

Alt + F4 and Ctrl + F4 won't work - Windows 7
Normally: Alt + F4 closes program; Ctrl + F4 closes file (or TAB in Internet Explorer); both stopped functioning on 12/06/2012 - no new software installed, no other known issues.
I also notice that pressing "Alt" alone toggles on and off the accellerator keys' letter underline indicators for items in the File menus (File, Edit, View, etc.).

This applies to all software I'm operating (that I've noticed thus far) under Windows 7.
...
any help will be appreciated ...

Keys to the Problem Alt + F4 and Ctrl + F4 won't work - Windows 7

Download Error Fixer (Free)

Hi Archer,
Thank you for posting in the Microsoft community.
From the description I understand that the short cut keys alt+F4 and ctrl+F4 are not working on the computer.
This could be a result of some corruption to the system files.
I would suggest that you run the SFC scan and check.
a.       Click Start.
b.      Type “cmd” in the search bar.
c.       Right click on Command Prompt in the list.
d.      Choose “Run as Administrator”
e.      Type “sfc /scannow” (Note: there is a space after sfc)
 
You can refer to the link provided to understand the logs generated by the SFC scan.
How to use the System File Checker tool to troubleshoot missing or corrupted system files on Windows Vista or on Windows 7
http://support.microsoft.com/kb/929833
 
If you need further assistance then let us know.

Manually editing the Windows registry

Caution: Unless you an advanced PC user, please do not edit the Windows registry manually.

Because of this risk, we highly recommend using a trusted registry cleaner such as SmartPCFixer Using a registry cleaner automates the process of finding invalid registry entries, missing file references (like the one causing your MACHINE_CHECK_EXCEPTION error), and broken links within the registry. A backup is automatically created before each scan, with the ability to undo any changes in a single click, protecting you against the possibility of PC damage. The best part is that repairing registry errors can also dramatically improve system speed and performance.

• Click the Start button.
• Type "command" in the search box... DO NOT hit ENTER yet!
• While holding CTRL-Shift on your keyboard, hit ENTER.
• You will be prompted with a permission dialog box.
• Click Yes.
• A black box will open with a blinking cursor.
• Type "regedit" and hit ENTER.
• In the Registry Editor, select the Error 0x9C-related key (eg. Windows Operating System) you want to back up.
• From the File menu, choose Export.
• In the Save In list, select the folder where you want to save the Windows Operating System backup key.
• In the File Name box, type a name for your backup file, such as "Windows Operating System Backup".
• In the Export Range box, be sure that "Selected branch" is selected.
• Click Save.
• The file is then saved with a .reg file extension.
• You now have a backup of your MACHINE_CHECK_EXCEPTION-related registry entry.

The next steps in manually editing your registry will not be discussed in this article due to the high risk of damaging your system. If you would like to learn more about manual registry editing, please see the links below.

Recommended Method to Repair the Problem: Alt + F4 and Ctrl + F4 won't work - Windows 7:

How to Fix Alt + F4 and Ctrl + F4 won't work - Windows 7 with SmartPCFixer?

1. You can Download Error Fixer here. Install it on your computer. When you open it, it will perform a scan.

2. After the scan is finished, you can see the errors and problems need to be repaired. Click Fix All.

3. The Repair part is finished, the speed of your computer will be much higher than before and the errors have been fixed. You can also use other functions in SmartPCFixer. Like dll downloading, windows updating and print spooler error repair.

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