Can't Sign Out Of Outlook In Browsers?

For reference this is in regards to Portal.Office.Com:

     My company is suffering from this same problem for weeks now as well with no acknowledgement from M$ that it's even a problem! This is a MAJOR security issue! I've got HR and corporate screaming at me because no one can reliably log-out of their accounts regardless of the workstation/account they use. About 1% of the time it actually works, the other 99% of the time when the user logs out it APPEARS to work fine, but as soon as the next user goes to log in it logs back into the previous users' account.

     Just like the OP I've tried every trick in the book to make the PC forget the account, but nothing seems to work 100% of time; the issue just seems to go away after a few hours (though I had at least one instance where the user logged off over 2 weeks ago and it still went straight into that account when the next person logged on.)

     As the admin, I have tons of issues with this myself. I have one account for administration, and one for day to day use. I log in as the admin to make some adjustments, log-out, log in as my normal account and I get errors saying "there is no e-mail account tied to your user account." Okay, so I'll use a shortcut to access sharepoint for example, appears to be logged in correctly, use the links to navigate to e-mail, ERROR: no email account attached to admin user! I'm not logged in as the admin anymore so why would it be trying to go to the admin's email? EXTREMELY FRUSTRATING! I've left plenty of "feedback" via the server tools but I get the impression M$ doesn't even look at these as all their updates seem to only be cosmetic or new features while ignoring constant major problems with existing resources (haven't been able to print e-mails without a 20 minute delay for weeks as well, but that's a lot less urgent that this...)

*The OneDrive trick people have mentioned here does nothing to help.

*Adblocker doesn't appear to matter as many of our workstations do not have it.

*Remember me / keep me logged in makes no difference; we instruct users to not use this anyways.

I had the same sign out problem. Clicking (right or left) on my avatar did nothing. I use Firefox w/Adblock. After disabling the adblocker for Outlook.Live and refreshing the site, I finally got the drop down menu that allowed me to log out. Microsoft & Outlook support was useless in answering the question. In fact, I found a Microsoft support page that said that you were no longer allowed to log out in Outlook 2016!

This works for me

I haven't had any recurrence of this problem -- not in Chrome and not in Firefox -- since I followed the steps above. Of course Outlook remains whitelisted in my Adblocker, which was probably Micro$oft's cunning plan all along.

I have the same issue.  When I used the Outlook.live.com (previously Hotmail.com) I click the avatar in the upper right corner but nothing happens.   I know that is the way to log out as the first commentor said to do but he did not address the issue you and others are having.

The problem I have is after clicking the avatar the dropdown menu does not show.  No matter how many times I click nothing happens. 

My solution to this problem I have added a book mark in the toolbar to click on.  Once Outlook.com reloads only then when I click the avatar and the dropdown menu appears and I may click 'Sign out'.  This is an added step but its a temporary workaround for me.  Can someone write some code that I can execute to sign out since the link in the website is not performing properly?

I am using Firefox with the Ad-blocker like many others.

I have addressed this issue with Microsoft.  No word yet if this is an issue with the site not playing nice or something I caused.