Keep Office 365 and Office Professional Separate

Murray Brown
Murray Brown used Ask the Experts™

I have Office 2019 Professional installed on my machine. I use Outlook for work. I now want to set up Office 365 separately and only use Outlook on Office 365 for a separate business. How do I keep the two entirely separate.
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Hardware Tester and Debugger
Hi there! :)

Unfortunately. in Office 2013 and afterwards, you can’t custom select which Office applications you want to install for the package. Additionally, trying to install more than one version will result in error messages and conflicts. You may refer to the following article as reference. For this problem, the only way is to play around with the .exe file that unpacks the contents.

byundtMechanical Engineer
Most Valuable Expert 2013
Top Expert 2013
I don't believe it is possible to have both Office 365 and Office 2019 installed on the same computer. Both of them have only Click to Run installations, and there may only be one.

As a general rule, there may only be one version of Outlook installed on a computer. The only exception is when you have one Outlook installed using a .msi installer and the other using a click to run installer. I briefly did this with Outlook 2013 (.msi) and Outlook 2016/Office 365 (click to run).

Office 2010, 2013 and 2016/Office 365 are installed on my computer. No error messages, no incompatibility. The trick is to install the oldest Office first, and make sure it gets all its updates before moving on to the next version of Office. I was also using the .msi versions of the Office 2010 and 2013 installers. The .msi installations may co-exist with a single Click to Run installation. On previous computers, I have had as many as five versions of Office in a single Windows virtual machine (but only one Outlook version), plus two more native Mac versions of Office.

I did not install Outlook 2010 or 2013 because I wanted only one version of it. I had no problem doing a special install and specifying that Outlook not be installed.

It is possible for Outlook to support multiple email accounts, each with its own inbox. You need to be constantly vigilant regarding which email account sends an email, however. If you want to avoid any possibility of sending a Company A email from a Company B address, I suggest using two different email clients, one for each company. For example, you might use Outlook for your day job and Windows Mail for your side business.
Murray Developer


Thanks for the advice
NoahHardware Tester and Debugger

You're welcome! Glad I was of help :)

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