You might have to do a Google search for that answer. I only saw the tool recommended on another forum about a similar problem to yours. I have never used it myself. Checkdsk didn't do any good I guess?
i don't know what to do after typing in checkdsk... there's a little flash like a window opens, but it's only there for a split second.
If you're typing it in, I think you have to type Chkdsk c: \f. The better way to do it is to find it in your system tools.
I found instructions for using it in Vista.
Access Chkdsk Through Windows Explorer
•Step 1
Place your mouse over the "Start" button and right-click to invoke a set of menu options. Click on "Explore" to open the Explore file management system.
•Step 2
Select the hard drive letter for which you want to run the Chkdsk utility. Right-click on the driver letter to invoke a set of menu options and select "Properties."
•Step 3
Click on the "Tools" tab in the "Properties" window. Under the "Error-Checking" section of the window, click the "Check Now" button. If you have User Account Controls enabled, a window will pop up asking permission to continue. Click "Continue."
•Step 4
Decide if you want Chkdsk to "Automatically fix file system errors" and to "Scan for and attempt recovery of bad sectors," and click "Start."
•Step 5
Chkdsk will not run if your Windows Vista computer is in use, therefore it will request you to schedule Chkdsk. If you click "Schedule Check Disk," it will run the next time you boot your computer before Windows is actually loaded. Turn off the computer and then turn it back on. At that point Chkdsk will run
If you still can't install the C++ package after that, you'll probably need to run the Installer Cleanup tool. From what I read about that, it gives you a list of what is or has been installed with the windows installer and lets you choose which ones to remove. Even though you have uninstalled C++ by the normal means there may still be registry entries for the installer that are preventing you from installing it again. In essence, they may be telling the machine that it is still installed.