Edit in Microsoft Office action blocked because source uses a sign-in method that may be unsecure

[afjaber]

Hi, has anyone else seen this new issue when trying to open Excel or Word files for edit using the "Edit in Microsoft Office" action under document-details page?  This action works with AOS.  To clarify, the URL ../alfresco/aos/ is added to MS Trusted Locations, including subfolders.  It has been working fine without issue for past 2 years.  Then, suddenly as of today 12/12/2023, the entire user base complained of this issue.  User base consists of people from differnet companies (i.e. clients and vendors have access), networks, devices, O/S, IPs, etc.  Wondering if this is due to recent MS Office update. If you've encountered, as well, how have you resolved?  Use of MS Office files is critical to the daily operation, so this is major impact.  Thanks in advance for sharing if you have any similar experience or insights.  

[ftarantino]

Hi,
our customers report the same problem these days.

Do you have any suggestions?

[afjaber · Accepted solution]

Luckily, we have figured out a way to workaround this issue per the following article from Microsoft to change the Windows group policy settings.  

https://learn.microsoft.com/en-us/DeployOffice/security/basic-authentication-prompts-blocked#version...

The GPO update has resulted in the blocked access error (due to Basic Auth setup) to be resolved for the time being until we have more time to look into changing from Basic Auth to Modern Auth.  Users can now use the Edit in Microsoft Office action the same as beforehand without error.

[stefanmanov]

Hi, 

These polices should be appliend on local ActiveDirecotry or on M365 tenant?

[donlund]

I was able to solve this by editing the Windows Registry wth following command 

REG ADD HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\16.0\Common\Identity /t REG_EXPAND_SZ /v basichostallowlist /d "HOSTNAME"

Change "HOSTNAME" accordingly.   This was for Office 16.

Alternatively, navigate to  HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\16.0\Common\Identity.  If the basichostallowlist value does not exist, right-click on the right pane, select New > REG_EXPAND_SZ (expandable string value), and name it basichostallowlist.  If need more than two locations use server1.localnetwork;server2.localnetwork.