Hello @Long, Alan ,
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This is expected behaviour. It occurs if you are trying to sign in using an Microsoft 365 account that is from the same organization as the Microsoft 365 account that is already logged in on your Computer or Office Desktop app.
Please following steps:
1.Sign out of the accounts (for the same domain) that are signed in, then restart that computer. If this solution does not resolve the issue, try the workaround below
2.Workaround: Remove the existing user account and all connected services from your Office profile, and then clear cached credentials that may be on the computer
Step1:Sign out of Office and then sign back in.
Sign out of Microsoft Office using any Office product: Word, Excel, PowerPoint, Outlook, etc.
- 1.Select File, and then select Account.
- 2.Select Sign out.
- 3.Close the Office product and then restart it.
- 4.Select File, and then select Account.
- 5.Select Sign in and use your credentials to sign back in.
Step 2: Remove the user account from your Office profile
- 1.On the upper-right corner of an Office app (Word, Excel, PowerPoint), select your name, and then select Switch Account.
- 2.On the Accounts screen, select Sign out.
- 3.Locate the account that you want to remove, and then select Sign out.
Step 3: Remove connected services from your Office profile
- 1.Go to File, and then select Account.
- 2.Under Connected Services, remove all the services for the existing account.
Step 4: Clear cached credentials on the computer
a.Edit the registry to remove cached credentials:
- 1.Select Start, select Run, type regedit, and then select OK.
- 2.On Registry Editor, locate the following registry subkey:
- 3.Select the Office account that you want to delete, and then select Delete.
- 4.On the Identity subkey, locate Profiles, right-click the same Office account that you located in Step 1 of this procedure, and then select Delete.
- 5.Select File and then Exit Registry Editor.
b.Remove the cached credentials in Credentials Manager:
- 1.Select Start, then Windows System, then open the Control Panel and select Credential Manager.
- 2.Under the Windows Credentials tab, locate the account that you want to remove and then select Remove.
- 3.Log off, and then log back in to the computer.
"Sorry, another account from your organization is already signed in on this computer" in Office 2013
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