Most of the times, MS Office credentials get corrupted due to the older version and following that your other Office products may start facing the error. One such error is asking you to Sign in OneNote (which you can download from(Office.com/Setup) repetitively. However, this problem can be solved by just updating the OneNote for Mac and iOS. But, if you still face the error, we are enlisting some steps to fix the Office corrupted credentials for Mac: Close all the running apps of Office except OneNote Log out your OneNote applications Access “Keychain” find all the items containing “Office15”. You have to log in each account (most probably very fewer items will be there) Hint: It appears with the long alphanumeric code like-“MicrosoftOffice15…..” Now, delete all the items, all the authentication credentials will be deleted Access OneNote by signing in Note: One credential is shared to all the Office apps, so you need to sign-in again after signing out Because of just OneNote consistently prompts you to enter your password, your iOS credential may get corrupted. Steps to fix the Office corrupted credentials for iOS:(office Setup | ) Make sure you have updated all the office apps in your iPhone since Office shares only single identity. In contrast, it may harm the identity Always try to clear your credentials Tap “Settings” in your iPhone Then select “OneNote” Go to “Reset OneNote” Now select “Delete Sign-in credentials” Switch on the toggle Turn off your OneNote Sign it again your OneNote For more information on how to fix the OneNote performance issues for Mac and iOS or how to download OneNote using www.Office.com/Setup, you can call the customer support number. They will be happy to help you.