TRYING to share for co authoring a WORD document with an outside 365 user - through my OneDrive-not working properly!!

Question

This is maddening...working with a new user outside my organization (40 year old daughter!) both on MacOS current version. Compelled her to BUY an O365 subscription because it was SO EASY to then work with - we could BOTH be real time co-authoring the Word docs she needed input on.

NO BUENO

So, to begin with, I made a ton of changes on a docvument she emailed to me in desktop Word app on my side, saved it to my OneDrive, and then invted her to full rights as an editor via the "Share" function in Word. She received the invitation in outlook - but each time she tries to "open" the file by double clicking it she gets the following (attatched screenshot!) "Selected user account does not exist in tenant '***Remove PII***' and cannot acces the application '00000003-000-0ff1-ce00-0000000000000' in that tenant The account needs to be added as an external user in the tenant first. Pleas use a different account."

I then tried just emailing her a link, which i copied and pasted from the "Share" dialog, into messages - she was able to open it.however ONLY in her browser - NOT in the desktop Word application which is what we really want to occur- by default going forward as well!!

How can I fix this so we can operate like it is supposed to (and I do already with several others) - just not sure why this is doing this for her, and I promise that I DID LOOK!!!

Will want to do this next with Excel file as well...

Kinda urgent so please HELP!

Answer 1

Hi

Good morning! I hope this message finds you well.

It's been a while since our last conversation, and I wanted to check in on how things are progressing with the issues we've discussed. Have you had a chance to review the answers we have provided?

If there is anything else, I can help you, please don't hesitate to get in touch. I would be happy to help.

Thank you
Vy-Ng – MSFT | Microsoft Community Support Specialist

Answer 2

Dear Michael, 

Good day! Thank you for reaching out to the Microsoft Support Community. I understand you're trying to co-author a Word document using the desktop app, but the recipient is only able to open it in the browser and receives an error when trying to use the desktop version. 

The error message: 

“Selected user account does not exist in tenant and cannot access the application '00000003-0000-0ff1-ce00-000000000000' in that tenant…” 

This happens when the recipient’s Microsoft account hasn’t been added as a guest user in your Microsoft 365 environment. While browser access works with a shared link, the desktop Word app requires the user to be recognized as a guest in your tenant. 

1. Add the Recipient as a Guest in Microsoft Entra (Azure AD) 

• Go to https://entra.microsoft.com.
• Sign in with your Microsoft 365 admin account.
• In the left menu, select Users > All users.
• Click + New guest user.
• Enter the recipient’s email address and name.
• Click Invite. 

They will receive an email invitation to join your organization as a guest. Once they accept, their account will be registered in your tenant. 

2. Ask Them to Sign Out and Back In 

After accepting the invitation: 

• Ask them to sign out of all Microsoft apps (especially Word).
• Then sign back in using the same email address that was invited.
• Now, when they open the shared document link, it should open in the desktop Word app without errors.

This issue occurs when Microsoft 365 tries to open the document in the desktop app, but the user’s account isn’t recognized in your organization’s directory. The browser version works because it doesn’t require the same level of authentication. 

This is a common scenario when sharing across different Microsoft 365 tenants and adding the user as a guest resolves it fully. 

If the issue continues after these steps, I may need to explore advanced diagnostics or escalate the case for deeper investigation. Please let me know how things go, and I’ll be happy to assist further. 

I’m here to support you, and I’ll do my best to make this process as smooth as possible. Thank you again for your patience and for working through this with us. 

Warm regards, 

Vy-Ng – MSFT | Microsoft Community Support Specialist