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image deleted for PII
are we allowed only 1 attached file?
I included the screenshot when I'm adding a new email account and it failed with Sign-in failed. But I am able to add the same email account with same server information to my Outlook on my iPhone. Also I have 3 other Comcast email accounts that are working on Outlook windows, so there is something about this particular email that Outlook doesn't like.
Using New Outlook on Windows for personal email, calendar, and contact management
I renamed OLK and OneAuth folders, the I restarted Outlook, I had to re-add 4 accounts, they all working fine. One failed, the same I am having problem before = ******@comcast.net. Like I said, I was able to add it to Outlook on iPhone. Also I was able to add it to Apple Mail on iPhone.
Sorry to hear that you are having trouble with this situation. First, sign in to https://connect.xfinity.com using the affected account, navigate to Settings > Security, and verify that Third Party Access Security is enabled. This setting must be checked to allow applications such as Outlook to access the mailbox. Second, Comcast has been transitioning email accounts to Yahoo Mail throughout 2026. If this particular account has already migrated, you must configure it using Yahoo Mail authentication and server settings rather than the original Comcast settings. You can review the official information here: https://www.xfinity.com/support/articles/yahoo-email-migration-overview
Could you please confirm whether you can sign in to the affected account through Xfinity webmail, whether Third Party Access Security is enabled for that specific account, and whether you have received or accepted an invitation to migrate it to Yahoo Mail? Also, when the sign-in fails in New Outlook, does the error provide any additional troubleshooting details or an error code? This would help narrow down the cause without affecting your four working accounts.