365 ADD ON

Question

365 ADD ON

laura pesce 0

how do I add an existing computer to my existing office 365 family account.

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2 answers

Your answer

Answer 1

EmilyS726 278.3K Independent Advisor

You shouldn't have to add a device in order to use the subscription.

Just go ahead and install. You can install on as many devices as you want, the catch is - you can only sign into the same Microsoft account at up to 5 devices AT THE SAME TIME.

Just go ahead and install.

Please go to https://account.microsoft.com/services

Sign in to the Microsoft account you used for the subscription.

You should then see your subscription listed. Find the option called "Install desktop versions of Microsoft 365 apps like Word, Excel and Powerpoint to your devices". It has a down arrow icon next to it.

Click on that. It should start downloading the installer file. Then you just need to run that installer file to install the apps.

laura pesce 0 Reputation points

2026-11-05T16:48:14.7566667+00:00

I have a unique problem. The computer I am trying to install my family plan on was once used by someone else, who had an office subscription that has expired. When I try to install my subscription, it just wants to have me pay to renew the old one of the prior owner of the computer, which I obviously do not want to do.
EmilyS726 278.3K Reputation points Independent Advisor

2026-11-05T16:50:54.3433333+00:00

Laura, thank you for the context.

When you launched the app, can you go to Files > accounts? If it allows you, does it tell you the full name of the name? For example, Office Pro Plus 2021, or anything else? This will help me provide you with proper uninstall instructions.
laura pesce 0 Reputation points

2026-11-06T12:30:40.53+00:00

I do not see that section on app. is it not possible for me to speak to someone on the phone?
EmilyS726 278.3K Reputation points Independent Advisor

2026-11-06T13:11:33.3333333+00:00

Unfortunately not from the public forum here.

Consumer support is via chat only https://support.microsoft.com/contactus

However, there are still some areas we can check and hopefully resolve this.

In the Office apps, such as Excel, Word, do you see on the upper right the user icon? Can you click on it and sign out and sign in with yours?

Answer 2

Install Microsoft 365 on the existing Windows computer and sign in with the Microsoft account that owns—or has been invited to share—the Microsoft 365 Family subscription.

If this is your own computer

On the computer, open a browser and go to Microsoft 365 Apps.
Select Sign in and use the Microsoft account associated with your Microsoft 365 Family subscription.
Select Install apps > Install.
Open the downloaded installer and approve the Windows prompt.
Wait for “You’re all set! Office is installed now,” and then select Close.
Open Word from the Windows Start menu, accept the license agreement, and sign in with the same Microsoft account if prompted. This installs and activates Microsoft 365; you do not need to register the computer separately.^1^

If the computer belongs to another family member

The subscription owner must share Microsoft 365 with that person; do not give them the product key or the owner's account credentials.

The subscription owner opens the Microsoft 365 Services & subscriptions sharing page.
Select Share.
Send an Email invite, or select Create link and send the resulting link.
The family member accepts the invitation and selects Join now.
On their computer, they sign in using their own Microsoft account, select Install Microsoft 365 on all your devices, and run the installer.^2^

Microsoft 365 Family can be shared with up to five other people. If the invitee is already in another Microsoft family group, they must leave that group before joining yours.^2^

If Office is already installed

Open Word or Excel and sign in with the account associated with the subscription. If a trial or purchase screen appears, check that Office is signed in with the correct Microsoft account rather than an account that has no Microsoft 365 product associated with it.^3^

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