try asking this question in Microsoft Answers forum http://answers.microsoft.com/en-us/windows/forum/windows_vistaRegards, Santosh I do not represent the organisation I work for, all the opinions expressed here are my own. This posting is provided "AS IS" with no warranties or guarantees and confers no rights.

this article may help: https://discussions.apple.com/docs/DOC-3601Don (Please take a moment to "Vote as Helpful" and/or "Mark as Answer", where applicable. This helps the community, keeps the forums tidy, and recognises useful contributions. Thanks!)

Also refer to the similar question here:http://answers.microsoft.com/en-us/windows/forum/windows_vista-windows_install/not-able-to-access-windows-installer-on-vista-64/0c88e13e-3b58-4d6f-b442-c0a897c29dea And please ask this queston in the proper forum. Thanks. Regards, MiyaMiya Yao TechNet Community Support

Also refer to the similar question here:http://answers.microsoft.com/en-us/windows/forum/windows_vista-windows_install/not-able-to-access-windows-installer-on-vista-64/0c88e13e-3b58-4d6f-b442-c0a897c29dea And please ask this queston in the proper forum. Thanks. Regards, MiyaMiya Yao TechNet Community Support

I have been attempting to download itunes on my computer my computer has all the requirements necessary to complete the download but when i atempt to launch the program needed it tells me that windows installer service could not be accessed i have been on the computer trying to fix the problem for 5 hours straight yet i have found no useful information. My windows installer is Windows Installer. V 4.5.6002.18005 and through further research i have seen many people have been experiencing the same problem with this program. i really need an answer cause i need it to download itunes and update my phone so i can actually use my phone again. My computer runs on windows vista also.

try asking this question in Microsoft Answers forum http://answers.microsoft.com/en-us/windows/forum/windows_vistaRegards, Santosh I do not represent the organisation I work for, all the opinions expressed here are my own. This posting is provided "AS IS" with no warranties or guarantees and confers no rights.

this article may help: https://discussions.apple.com/docs/DOC-3601Don (Please take a moment to "Vote as Helpful" and/or "Mark as Answer", where applicable. This helps the community, keeps the forums tidy, and recognises useful contributions. Thanks!)