M365 Office Licensing Error 53003: Your sign-in was successful but you don’t have permission to access this resource

When opening an Office application on a Windows, Mac or iOS device, if you see the error 53003, which corresponds to “Your sign-in was successful but you don’t have permission to access this resource” or “Another user from your organization is signed in on this device” then the solution is described here:

https://learn.microsoft.com/en-us/office/troubleshoot/activation/another-account-already-signed-in

Here are the solutions, by platform:

Mac:

1. Close all Microsoft 365 apps.

2. Open Terminal and paste in this command and hit enter:

defaults write com.microsoft.Word ResetOneAuthCreds -bool YES

3. Sign back into the M365 apps.

Windows:

1. Sign out of all Microsoft 365 apps

2. Remove all folders in the following locations:

%localappdata%\Microsoft\OneAuth

%localappdata%\Microsoft\IdentityCache

You can access these folders by copying the path listed above, click on the start menu, paste in the path and hit enter.

3. Then sign back into the Microsoft 365 apps.

NOTE: You can also accomplish this from a Command Prompt (with Run with Admin Privileges) with the following commands

cd %localappdata%\Microsoft
rmdir /s OneAuth\* IdentityCache\*

iOS/iPadOS:

1. Go to the Settings app > Microsoft 365 (Office) settings > Reset Microsoft 365 (Office) > Enable "Delete Sign-In Credentials" and "Reset Cloud Settings".

2. Sign Back into the Microsoft 365 Apps.

NOTE: If you have an older version of Office apps installed, you may need to follow this process with each individual application (Word, Excel, PowerPoint and OneNote).