Unable to add my Office 365 account to Outlook

Outlook client version: Microsoft Outlook 2016 MSO (16.0.8625.2121) 32-bit

Yes I have the CNAME record.

As I said, using autodiscover with the Windows Mail client (on the same computer, connecting to the same account) and my Android phone works flawlessly. This is purely an Outlook problem.

Result of Remote Connectivity Analyzer says: Autodiscover was successfully tested for Exchange ActiveSync.

There is a single warning sign saying:

	Analyzing the certificate chains for compatibility problems with versions of Windows.
	Potential compatibility problems were identified with some versions of Windows.
	Additional Details   The Microsoft Connectivity Analyzer can only validate the certificate chain using the Root Certificate Update functionality from Windows Update. Your certificate may not be trusted on Windows if the "Update Root Certificates" feature isn't enabled. Elapsed Time: 7 ms.

Further information.

I just logged into a dummy-useraccount on the same PC, with the same version of Outlook.

Plotted my information in, and the connection was made without any issue at all.

So it is pretty clear to me that the problem is with my Windows User Account, but how I fix it is a mystery to me. Hope to get some suggestions, as I would prefer to keep my account instead of setting up a new one.

Some further info:

When I use the Outlook Test of automatic configuration (free translation from my native language), the useraccount where the mail can't be set up results in:

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=401

This happens only for my primary windows user account.

On a dummy-account for windows, the result was:

GetLastError=0; httpStatus=401

GetLastError=0; httpStatus=200

And then it worked!

And this was only a different windows user account. Same PC, same Outlook version, same Office 365 account.

Something on my primary user is causing this 401 to repeat itself and never succeed.

The support and recovery assistant can connect to my Office 365 without a problem, and it appears as if it thinks the account is set up as it should. 

I have considered if it could be some local firewall policy for my user account, but I don't know what to look for.

Hello Shyamal,

I agree completely with you, the problem is with the windows user account, since same computer, same account, same outlook client, works fine on a different user account.

Thank you for the suggestion about updates, I have updated both Office 365 and Windows 10 now. Unfortunately the problem persists.

I have used a temporary solution - setting the account up as IMAP - instead of Exchange. This gives me access to my emails from outlook, but it is not a good longterm solution. Interestingly enough, even though it is the same user and the same password, IMAP works fine, though Exchange doesn't.

I would really appreciate it if you could point me to some diagnostic tool, that I can use to make a comparison between the POST data that is sent from the user account where it works, and the POST data that are sent from the user account where it doesn't work.

I suspect the data are changed by some proces, maybe grabbing the password from my personal microsoft account, even though the email has been removed from this account some days ago.

Another option could be that the data are changed completely or not transferred completely by some process that interfere with the data transfer, perhaps and extremely low timeout setting somewhere (I just don't know where).

Shyamal,

Great suggestion about the clean boot. I tried fail-safe, but that was not sufficient.

I followed the guideline and deactivated all startup services, did a reboot, but with no luck.

Then I cleared all passwords in the credential manager, also with out any luck.

My thoughts: I am stopping everything other than Microsoft services, but I have the theory that it is a Microsoft service that contributes to the problem, by continuing to mix up my personal and business accounts, even though my primary email has been changed

Sincerely,
Søren Skjold Andersen

Hello,

That shouldn't be your user mailbox issue, since you can successfully configured in  dummy Windows user account on the same PC.

You can run sfc /scannow command that will scan all protected system files, and replace corrupted files. https://support.microsoft.com/en-us/help/929833/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system

Manually remove a Click-to-Run installation of Office, it will delete the Office registry subkeysand then reinstall - https://support.office.com/en-us/article/Manually-uninstall-Office-4e2904ea-25c8-4544-99ee-17696bb3027b?ui=en-US&rs=en-US&ad=US

Did you change your password to check your issue? Change the password and then check. Sometime it might be changing password take longer time then you expected to replicate on the server side for Outlook client. It can take upto 24 hrs wait then try again.

Hope this may help you.

Elsa,

I don't see how sfc /scannow would help. Since I can connect to the mailbox on a different useraccount, the system files should be fine, shouldn't they?

I have already removed CtR Office manually, deleted registry keys and everything, reinstalled it, but to no avail.

Have tried changing my password, but also without effect.

Further information: When I run the outlook test on autodiscovery it doesn't work with my own credentials, and it doesn't work with any of my colleagues credentials, so apparently it might not be an issue with my personal microsoft account.

It is some general problem sitting somewhere between outlook (because any other windows program can log onto office 365 without a problem, just not for autodiscovery) and my windows user account.

At some point I was wondering if it could be a cached certificate of some sort, but I wouldn't know what to look for.