1. Use Office 365 online
If you really need to use your Office 365 account and you don’t have enough time to try to troubleshoot this issue, you can access Word or Excel online. Error code 700003 prevents Office apps from running on the desktop, but everything should work just fine online.
2. Disconnect the problematic account
Disconnecting the account that triggered error 70003 is another quick solution that could potentially solve this problem.
>>Open the Settings app
>>Go to Accounts
>>Select Access work or school
>>Find the account that you can’t use and select Disconnect
>>Wait until the account is disconnected
>>Try to login to Office again using your regular username and password
3.Delete the problematic account
If disconnecting the account didn’t work, you can try to delete it from your computer.
>>Launch the Settings app
>>Navigate to Accounts
>>Select the Access work or school option
>>Delete the account
>>Sign into your Outlook profile again.
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