MS Office no longer support Basic Authentication in WebDAV

I am using WebDAV 2.6.2 in my Cuba 7.2.20 project.
When I use Word in Office 365 to access a document via WebDAV, I am now getting an error message that is telling me that Office is blocking access to the webDAV url because the source uses a sign-in method that may be unsecure.

When I dug deeper, I see where MS Office no longer supports Basic Authentication in WebDAV

This will now cause a problem when using recent versions of Word and the WebDAV addon.

Is there a solution to this ?

Am I the only one having this challenge ?


Yes, such a problem exists and we will try to implement generic solution for that.

As a possible WA you can try to enable basic auth prompt for some specific hosts via policies - Basic authentication sign-in prompts are blocked by default in Microsoft 365 Apps - Deploy Office | Microsoft Learn - or via registry:
Key: HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\16.0\Common\Identity
Value: basichostallowlist

  • type: REG_EXPAND_SZ (expandable string value)
  • data: semicolon separated list of hostnames (e.g.:;

Also in case of version of Office what still allows basic auth but shows warning about it there is another issue: if warning is disabled via “Do not show again” checkbox documents will not be opened anymore for some reason. To fix this you need to ‘revert’ this checkbox via registry - set 0 to BasicAuthSuppressWarning value at the same key (HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\16.0\Common\Identity)