Once you can meet the problem, that all applications fails during installation. You can receive different errors, but all they have common source, and this source is Windows Installer. Windows Installer is a service, that any program can use to install itself to your system. Actually it consists of a few files, that can be easily repaired.

To reinstall the Windows Installer, follow these steps.

1. Click Start, and then click Run.

2. In the Open box, type cmd, and then click OK.

3. At the command prompt, type the following lines. Press ENTER after you type each line.

cd %windir%\system32

ren msi.dll msi.old

ren msiexec.exe msiexec.old

ren msihnd.dll msihnd.old

4. At the command prompt, type exit, and then press ENTER.

5. Restart your computer.

6. Update the Windows Installer files to the latest version. To do so, visit one of the following Microsoft Web sites, and then download and install Windows Installer 2.0.

Note Windows Installer 2.0 is included with Microsoft Windows XP. You do not have to perform this step if you are using Windows XP.

For Windows 98, Windows 98 Second Edition, and Windows Millennium Edition: http://www.microsoft.com/downloads/details.aspx?FamilyID=cebbacd8-c094-4255-b702-de3bb768148f%20&displaylang=en 
For Microsoft Windows NT 4.0 and Microsoft Windows 2000: http://www.microsoft.com/downloads/details.aspx?FamilyID=4b6140f9-2d36-4977-8fa1-6f8a0f5dca8f&DisplayLang=en

After the installation of the Windows Installer is complete, shut down and restart your computer normally.