Outlook recurring error

[geranium]

I've got an unpredictably recurring error on a customer's Windows 10 machine. It first occurred when they added their Microsoft account to the Outlook client. After a month, or a week, or a few days of running correctly, Outlook will fail to start with the message:

"Outlook cannot log on. Verify you are connected to the network and are using the proper server and mailbox name. The Microsoft Exchange service in your profile is missing required information. Modify your profile to ensure that you are using the correct Microsoft Exchange information service."

Outlook was initially installed in 2014 through an Office 365 Personal subscription, and has been kept up to date ever since. There are two IMAP accounts, one data file with old emails and the MS Exchange account. If I remove the MS account, Outlook will run fine again and I can then re-add the MS account and all will be well until the error recurs days or weeks later.

At this point I have it running fine, but it may fail again, so if anyone has any insight and can point out something I have missed, I'd be glad to hear it.

What I've done:

1. Update Outlook - still fails
2. Outlook repair - still fails
   
3. Create a new profile - still fails
4. Remove and re-add MS account - still fails

Most recently (today), I have:

1. Run chkdsk which made some modifications
2. Checked for malware - looks clean
   
3. Uninstalled Office fully
4. Reinstalled Office from offline installer downloaded from the customer's Office 365 Personal account
5. Added this registry key based on this: https://support.microsoft.com/en-us...e-365-outlook-doesn-t-connect-or-web-services
   HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Autodiscover
   DWORD: ExcludeLastKnownGoodUrl
   Value: 1

So it's running fine at the moment, but I'd love to know if there is something else I should check to improve the chances that it keeps running properly.

 

[seashore]

Maybe test the account concurrently on another machine for however long it takes. If all good, may be time to nuke and pave your customer's machine.

 

[frase]

How many systems do they have, If one no need for 365. Is Win10 current 1909? Paying for 365 for one account is useless. I would install Office 2019 H&B if that is the case and own outright.

 

[geranium]

Good point. They are using it on their phone as well, but just for the calendar as far as I know, so they probably don't need 365.

 

[frase]

Yes 2019 gives an option to install on Mobile app as well. No subscription own outright on one System.