Have you tried repairing the Office installation? That said, Office 2007 is no longer supported, so upgrading would probably be a good idea, as in some respects the later versions are significantly better products.

There is generally little reason to use 64-bit Office and, depending what addins you use, potentially good reasons for not doing so. Not all addins are 64-bit compatible and the only real advantage with 64-bit Office is for working with exceptionally large Excel workbooks.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

I ended up purchasing a valid copy of Microsoft Office 2016 Pro Plus from a (sealed) Microsoft USB key. Once installed the product validated. I then had the MS Office 2016 was checked out by Microsoft and MS confirmed it was legit as I had purchased it from a eBay seller (~2650+ - 100 percent positive feedback) I just wanted to make certain it was legit copy as there's copies of MS Office being illegally sold on eBay that aren't legit)

First nninstalled all copies of Microsoft Office and then installed Microsoft Office 2016 Pro Plus and now everything is ok.

Note: If you have other versions of Microsoft Office Installation installed on you PC. The Microsoft Office installer won't uninstall them and one or installations may interfere with the current installation. So it's better to uninstall all versions when installing a new version as to have two or more versions installed potentially causes problems.

Whilst Office will allow you to keep your older version (except for Outlook), having multiple versions installed is unlikely to cause any problems. Indeed, developers who support multiple Office versions are likely to need this. IIRC, Charles Kenyon, a regular contributor here, has all versions back to Office 2003 installed.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]