Microsoft Teams guest users cant access files

Hi All.

We have enabled guest users from external organization.

The guest users can access a Teams. But they can’t view files within File Tab

1. Teams Admin Centre >> Guest Access is turned ON.
   
   
2. M365 Groups have been checked.
   
   
   
   
3. SPO Site for that that Teams has following settings
   
   IMAGE
   
   NOTE: There is only Blocked Domains and not additional domain for this setting. 
   
   
4. SPO sharing options have been configured like this:
   
    
   
   
   
5. User is added in AAD
   
   
   
   
6. But use claims he access Teams but NOT access files tab
   
   
   Microsoft teams.  Access denied.   You do not have permission
   
   
   
7. I did tried reproduce it and I got the same Access denied message in one my test tenants. 
   
   
8.   But when I add Allowed domain in SPO for that site
   
9. The Guest access (testing with my outlook.com) works. 
   
   

Its  not documented in Microsoft Teams to add domain SPO Admin Centre for guest access 
https://docs.microsoft.com/en-us/microsoft-365/solutions/collaborate-as-team?view=o365-worldwide

Please advice what I am is missing here. Thanks in advance.

adam deltinger  ChrisHoardMVP  ChrisWebbTech