Anything is possible, but whether it's probable is another matter entirely. Given how rare it is for people to have compatibility problems as a result of having multiple copies of Office installed, I'd say your concerns are rather overblown.

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

I've been running MS Office since Office 96/97 and can't remember having any problems with versions since, except for ver. 2007 under Wndows 10. Is one reason why I upgraded to a later version(s) as I noticed some strange behavior from Outllook 2007 under Windows 10.

After the final upgrade to version 2016 I've not had any problems. One earlier version I did have problems with the validation and was required to completely remove this installation as well as the 2007 installation in order to install ver. 2016. It was suggested by several people to completely remove MS Office from my PC before the final installation of ver. 2016.

So I think perhaps most people don't have any problems with MS Office and even running multiple installations. However there are a few people who do, which is not a common occurrence.

When I contacted Microsoft support in order to question the legitimacy of the MS Office purchased from an eBay seller I was told there were many illegitimate copies being sold on eBay.

To check the Office 2016 version installed on my PC they had me download and run a remote program that allows them to take over my PC remotely (after giving them permission). They then perform various tests of the Office installation checking files, etc. MS also checks the validation key code which I provided.

Everything tested ok as one hundred percent legit.

Some people do have problems with MS Office installations. If you sift through some of the forums and the Microsoft website you will find people who have had problems with their installation for one reason or another.

It's often suggested when having problems related to ms office is to completely uninstall. There is a utility program that can be downloaded from microsoft.com that will uninstall all versions of MS Office installed on your PC. There are also instructions on how to manually uninstall MS Office from your PC, completely deleting all traces of it's installation(s).

It's sorta like something doesn't seem like a problem until it actually happens to you, then it becomes a problem.

E.g. my car runs and runs just fine for years, as I maintain it, everything is ok. Until something breaks and becomes problem.

Often, quite inappropriately... You'll not find many recommendations to do that on this or most other forums I support.

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

No the status quo recommends to repair Microsoft office however there are issues running multiple copies of ms office together that sometimes arise.

Usually recommendations such as to repair office are normally recommended before re-installation, DE-installation of previous versions, etc. but under some circumstances people who work for Microsoft have recommended to un-install same and other versions of ms office before proceeding installing or re-installing the same or newer versions.

I'm don't believe Microsoft employees are being inappropriate when they have at times under certain circumstances recommended uninstall other or all version of Microsoft Office installed on a PC.

If somethings not part of the status quo doesn't mean it doesn't exist.

If you want to install and run more than one version of Office on the same PC, here are some tips to help you avoid most set up errors:

"Install and use different versions of Office on the same PC"

https://support.office.com/en-us/art...7-b78c513788bf