Let’s begin by understanding how windows programs work. All files on windows have a program that runs and opens those files for viewing even if you might not have it on your PC yet. The extension determines which program opens it e.g. .doc or .docx are opened by MS Word and .txt or .inf are opened by notepad. What you should know is that whenever you install a program, they not only get copied to the standard ‘program files’ folder. Keys, shortcuts and extensions the program can open are copied to the .exe registry. If you lack the software to open a file on your PC, windows will bring up a pop up dialog box asking you which program to open with. This is because the file you are trying to open has an extension that is not associated with any programs in the registry. This is why just copying a program from another computer to your storage space will not detected the files it opens automatically. There might be a rare time when everything fails and even the programs you are sure are on your PC, no longer function. The simple reason for this is that the .exe registry has been altered. This might be as a result of several things. The registry might have been corrupted by a hard disk failure. This could be from power losses, overheating of the drive, or bringing magnets in close contact with your computer. It could also be a virus or malware affecting the registry. This is why you should always have your antivirus updated regularly. Some virus or malware (usually from shareware and freeware) aim at destroying your registry. Now what you left with is a bunch of programs that are not associated to any file. So whenever you try to open a file, it will ask for the associated program. Your programs might also stop launching after a virus scan. This is because some viruses had embedded themselves in your registry. After scanning your registry using an antivirus, a big chunk was found to be infected and was quarantined or deleted. All associated file extensions were wiped along with them leaving your computer without knowledge of what opens what. Sometimes, installing a new and genuine program might upset your registry. The LEXMARK wireless all-in-one has been associated with this problem severally. This could be because of bad input into the registry, which scrambles up the rest of the registry. Whatever the issue is on your Windows Vista, here are ways to restore the functionality of your computer. All ways are aimed at restoring the health of your registry so that your files can find the programs associated with their extension.
Method 1: Use ExeFix Vista to fix the registry
This will fix your registry by copying in new definitions for your programs.
Method 2: Uninstall the latest programs before the issue begun
If this problem begins after installing a new program, uninstall it because this might be the issue. If you are not sure which program it is, uninstall all latest programs and any suspicious ones to remove them from the registry. To uninstall a program:
Method 3: Restore Windows back to the last time it was functioning normally
Restoring windows to its previous know functioning state will fix your registry. If you regularly back up your PC for restoration, just follow these steps.
You may lose programs that you installed before that day but your data will be intact.
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