Accessing Outlook on the web for business using organizational credentials.
Dear UMAS FINTAX,
Thanks for choosing Microsoft Community.
Based on your description, do you mean that you need to log in three accounts at the same time in Outlook on the web? If so, it is the normal scneario. We can only log in one account in the same browser. If you open outlook on the web again in normal window of this browser, this account will be logged in automatically.
And for this, please be kindly to try to log in one account in normal windows. And then use the same browser with Inprivate windows and check whether you can log in your other two accounts at the same time. Here is the way to do this: Right click the Browser>Open in Private Winsows and then check the result.
If there is any update, please feel free to let me know. I will continue to help you based on the information you provide. Your understanding and co-operation are highly appreciated.
Thanks for your precious time. Have a nice day.
Sincerely,
Katherine