Outlook Login Failed And Repeatedly Requested A Password In Office 365

I have discovered that many users can not sign into their outlook app. One, in particular, is having some issues using Outlook with Office 365. When they launch outlook, they are greeted by "connecting to: user@domain.com" and a password request from windows security.

This is because Microsoft has made modern Auth mandatory and deprecated basic Auth. Additionally, some versions of office still contain an outdated Registry Key that forces modern Auth to be OFF.

The solution listed below is the only one that resolved the problem for the people who are experiencing it.

Solution - Outlook Modern Authentication Registry Settings

Setups to follow to solve this issue,

  1. Open the registry editor as the client (This should not be done as adminstrator as it will apply the changes to your profile instead of the client's settings).
  2. Find a path to HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity


     
  3. Verify if there is a DWORD value Named "EnabledADAL" that is set to 0.
  4. Update the DWORD value for "EnabledADAL" to 1.
  5. Select OK
  6. Verify if there is a DWORD value Named "DisableADALaptopWAMOverride" that is set to 1.
  7. Update the DWORD value for "DisableADALaptopWAMOverride" to 0.
  8. Select OK
  9. Close the registry editor and sign in to Outlook.