error message trying to update iTunes version 12.9.3.3 to 12.9.6

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. When reinstalling right click on the downloaded setup file and use run as administrator. It may also help to temporarily disable any non-Microsoft anti-virus.

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, or want to revert to an older version if the current one won't work properly for you at the moment. Links to the most recent builds are now at the bottom of the page.

Your library and device backups should be unaffected by these steps but there are links to backup and recovery advice should it be needed.

tt2

The first line is a link to an article where most of the advice given in later points is located. For historical reasons the steps for removing and reinstalling iTunes is in the second main section of the article, even though it is probably the most used part of it. Removing and reinstalling the iTunes application should have no impact on your iTunes library which is stored in a different area of your hard drive. This point is also made in my original post. The article has detailed steps for removing and then reinstalling iTunes which should cover nearly all eventualities you might encounter while trying to remove the iTunes components that are already installed, or that arise while installing a fresh copy. That said I'm more than happy to take follow up questions if you get stuck as you work through it. If I had a more focused approach to offer in respect of the error message I would offer it, but in this case a tear down and rebuild is the best suggestion. As noted there is also recovery advice for any potential library corruption that can occasionally occur during an iTunes upgrade, and a guide to taking and maintaining a security copy of your library.

tt2