Hi FUKKOIOO,
>> I have an issue with a few clients of mine where Outlook keeps prompting for a users password.
By this, do you mean this problem affect some of the users in the same environment?
Generally, the reasons for this issue can be various. Apart from the steps you have mentioned above, it is also suggested to try to temporarily turn off your antivirus software to check if the issue will be gone.
Besides, hopefully the other troubleshooting steps in the following forum article can be helpful:
Why does Outlook keep prompting for password
As per your concern about the recent update, could you please collect the detailed build number of both Outlook and Windows system then we can do further research on this?
Any findings, please post back at ease.
Best regards,
Yuki Sun
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