On ship using Starlink Internet connection - Mail client on phone returning authentication error AAADSTS165000

Question

Hi:

I have (2) users on a ship using Starlink for Internet. For both users, the email client on their iPhones stopped syncing email and is returning an error: ADSTS165000: Invalid Request: The user session context is missing. One or more of the user context values (cookies; form fields; headers) were not supplied, ...

Thanks for any insights on how to resolve this issue!

Bob H.

Answer 1

Hi @BobH-3096

Welcome to our forum!

Looks like the issue is more related to Outlook for mobile. Please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. In order to better solve your problem, it's suggested to post your issue on this dedicated forum for Outlook for Mobile for more professional help.

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Based on my search, this error code ADSTS165000 indicate that there is a problem with the authentication process, there are many reasons why this can happen, here are some steps to help resolve the issue:

Clear the cache and cookies on the email client.

Ensure that the date and time settings on the iPhones are correct, as incorrect settings can cause sync issues.

Update your Outlook client to the latest version.

Additionally, since the users are on a ship using Starlink, it’s important to ensure that the internet connection is stable, as intermittent connectivity could also lead to such errors.

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