Hello facedown,
There are a couple of things you can try to see if it helps.
One, run SFC /scannow to see if you have any corrupt system files in Windows 7.
Click Start
Type: CMD, from the results, right click CMD
Click 'Run as Administrator'
At the Command Prompt, type: sfc /scannow
This will check for any integrity violations and fix any corrupted operating system files.
Restart your system.
KB Article ID: 929833 -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
Then try and see if you are still not able to open Windows dialog boxes. If not, then I would think your next option would be to do a In-Place upgrade which repairs Windows 7.
However, you will need to have the Windows 7 DVD.
The In-place Upgrade is a tool to repair the system. Through the special upgrade process, we will be able to repair the system. The In-place Upgrade will not affect settings like photos, movies, documents, etc. that are saved on the computer. Though this operation will not remove or modify the installed programs and files, I still suggest you backup the important files before doing this. In addition, you may have to reinstall the device drivers after this operation.
The detail steps are included as below:
In-place upgrade
====================
- Log on the system first.
- Insert the Windows 7 DVD in the computer's DVD drive.
- Click Start and choose Computer.
- Find the "setup.exe" file in the DVD-ROM and double click it.
- Click Install now.
- When you are prompted to input the product key, please click Next directly without inputting any key. The setup wizard will prompt and asking if you confirm to install Windows 7 without the key and please choose to confirm.
- When you reach the "Which type of installation do you want" screen, click Upgrade to upgrade the system files of Windows 7.
Note: While performing the in-place upgrade, the system will restart automatically (Several times) to merge the files and programs, please leave the computer alone and do not configure it until the "in-place upgrade" completed. The system will start Windows 7 once it is upgraded. Once the computer is performing "in-place upgrade", you can go away and leave the computer and it will complete automatically.
Please reply back with an update and let us know if this helps.
Sincerely,
Marilyn
Microsoft Answers Support Engineer
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