Active Sync 4.5 is the last version released... Get it here. forums.windowscentral.com/e...
I would run it in Compatibility Mode for XP Service Pack 2 (SP2).
More details here as well: https://en.wikipedia.org/wiki/ActiveSync
Note that there is a hard line in Office Products drawn at 2003. Pre 2003 documents/files/etc need to be converted to work with more modern versions of Office (2007 and up). Outlook is considered an Office product.
You may benefit from installing the Office File Converter Pack. See this page: https://support.microsoft.com/en-us/kb/212265
However, it may still not all come together. They built those iPAQs so well they have outlived their support for many years. I still have a functional iPAQ rx3115 in a drawer. It's pretty much functional, but just an oddity now.
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