Microsoft Teams - Create a read-only folder so that participants cannot edit your documents

If you want to place documents in one specific folder and want all files in this folder to remain unchanged. Then take a look at this manual.
Also readCreating a guest team and restricting the use of the general channel - Read-Only
Create a read-only folder so that participants cannot modify your documents
Guests can use your general channel by-default with almost as many rights and possibilities as an teams owner. To protect this, you can disable document sharing.
In the general channel for files, press - Open in SharePoint

Set the site members to read only via "Site permissions".

Example screenshot. The guests cannot post documents in the General team.
The owners for Project Y can post documents in the General channel.

Alternative instructions: Create a read-only folder in Microsoft Teams (365tips.be)
Creating a read-only folder in teams for education
Within education teams you have a "read only for students" in the general channel. You can still use these instructions for other channels. There are deviations in default settings for education and for regular Office 365 tenants.

Test and validate that all settings are correct?
- Login with your test account at Teams. (User 365 is a member of this organisation-wide team)
- Navigate to your Teams.
- As you can see, a pop-up appears saying that this folder is read-only.

Also read: How to prevent users from deleting channels, tabs & apps in Teams
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