How to Use Office 365 and Office 2019 Together?

There are several users who want to work with Office 365 and Office 2019 together. However, it is not as easy as it looks, as there are several factors that come with like Office edition, installation technology, and system architecture. Therefore, in this guide, I will explain how can Office 365 and Office 2019 coexist.

For different users, Microsoft provides multiple Office editions to meet different needs. Microsoft 365 is a subscription-based program, and Office 2019 is a one-time purchase. Both can be used together for their own work. But it requires several arrangements.

Difference Between Microsoft 365 and Office 2019

Before using them together, you must know the differences between them.

Can Office 365 and Office 2019 Coexist? Full Explanation

In most cases, it is not possible to use both Microsoft 365 and MS Office 2019 on the same computer. This is because the installation program of Microsoft will block the setup to prevent system crashes, overlapping file registries, and licensing errors.

But there are three rare scenarios where you can use both on the same machine.

Scenario 1: App Exclusive Setup
In Microsoft compatibility rules, you can combine the two versions as long as they do not overlap with Office applications. For this, you have to customize the deployment so the same app is not installed twice. For example, you configure the installer on your local drive that contains Word, Excel, and PowerPoint from Office 365. But you must only accept a publisher from Office 2019 Professional.

Scenario 2: Windows Sandbox or Hyper-V
Keep your one program in a virtual container that is built directly in Windows 10 or 11.

Scenario 3: Mixed Local and Web Deployment
It is a common case where you run the desktop version with its web counterpart.

If you are under these three scenarios, then you can install both together, but you must apply the following conditions.

• Both Office 365 and Office 2019 must use the same architecture (32-bit or 64-bit)
• They must be installed using compatible installation technologies.
• You can’t install conflicting versions of the same application.
• You must fulfill the licensing and activation requirements of both of the programs.

What Would Happen If Microsoft 365 were installed over Office 2019?

You already have installed Office 2019, and you are attempting to install Microsoft 365 in addition to that without you clean the uninstalling it. There are two outcomes arises.

Outcome A: Office 2019 will be replaced
If you download the installer directly from the online Microsoft 365 portal dashboard. Then it recognizes the shared core architecture. The following things will appear.

The installer of Microsoft 365 overwrites the permanent code of Office 2019 with the subscription cloud files.
It only removes the application. Your documents, or local Outlook data profiles, should not be deleted or modified.
After that, your existing desktop shortcuts will remain where they are. But when you launch Word or Excel, the Microsoft 365 screen splashes.

Outcome B: Installation Fails
If you try to install a retail disc or a standalone offline package while Office 2019 is still active. Then the installer will freeze, and a pop-up window appears stating “Stop, you should wait to install Office. We’re sorry we can’t continue because we found an existing product.”

How to Install Office 365 Without Affecting Office 2019?

To securely install your Microsoft 365 on the same computer as Office 2019. You have to first check the important rules and then follow the installation steps.

Key Points to Remember

• You must have these installation models
• Office 355 typically uses the Click-to-Run installer
• Office 2019 retail also uses Click-to-Run, and volume-licensed Office 2019 uses MSI.
• Microsoft does not support installing two Click-to-Run suites side by side and on the same Windows profile. It creates conflicts.
• MSI-based and Click-to-Run can be used to install the programs.

Practical Tips

• Use a virtual machine or a separate physical machine to keep one suite.
• Don’t use Windows user account isolation because Office products share system components, and it will create conflict.
• When you are using volume-licensed MSI Office, you can install Microsoft 365 click-to-Run side by side. First, confirm with IT or licensing.
• Before you install Office 365, uninstall Office 2019 to avoid mixing.
• The web and mobile app of Office provide you access without locally installing.
• Complete uninstall of the existing Office. Go to Settings >> Apps or Microsoft Support and Recovery Assistant.
• Properly use the account or product key during activation.
• Also, keep a backup of your data before uninstalling Office 2019.

Now, you can install Microsoft 365 by following these steps.

How to Install Microsoft 365 Installer?

1. In the browser, go to the Microsoft 365 official site.
2. Log in with your Microsoft account with your subscription.
3. Click on the Install apps on the account dashboard home page.
4. Select Install Office or Install Microsoft 365 apps. Download the 64-bit version.
5. Now, then install the suite and click Yes when asked Do you want to allow this app to make changes to your device.
6. Properly complete the installation.

Can you Upgrade Office 2019 to Office 365?

Yes, you can upgrade Office 2019 to Microsoft 365. Previously, you replaced the existing Office 2019 with Microsoft 365. But, many businesses want to move from Office 2019 to Office 365 for the Teams integration, OneDrive storage, and other beneficial features. For an easy process, use SysTools IMAP Migration Tool.

Conclusion

It is possible to work with both Office 2019 and Office 365 together. So, do Microsoft 365 and Office 2019 coexist? Yes, in some cases. Here, I have explained scenarios where you can use the suites together. I also provided steps to install Microsoft 365 without affecting Office 2019.