AppleApplicationSupport64.msi
Where can I download AppleApplicationSupport64.msi?
iPhone 4, iOS 5.1.1, Windows 7
It isn't available as a standalone download. You can extract it from the main iTunes installer if needs be, however if you have an error message about it then you may need the advice at Missing MSI errors.
For general advice see Troubleshooting issues with iTunes for Windows updates.
The steps in the second box are a guide to removing everything related to iTunes and then rebuilding it which is often a good starting point unless the symptoms indicate a more specific approach. Review the other boxes and the list of support documents further down the page in case one of them applies.
The further information area has direct links to the current and recent builds in case you have problems downloading, need to revert to an older version or want to try theiTunes for Windows (64-bit - for older video cards) release as a workaround for performance issues or compatibility with third party software.
If you cannot get the current build to work roll back to the previous one.
Your library should be unaffected by these steps but there also links to backup and recovery advice should it be needed.
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