Hi @Michal ,
Is the template PPT file you are talking about like this?
How did you set it to Read-Only? Through Permission?
I set unique permission for the library containing the PPT file. Except for the site owner, everyone has only read permission. The situation of opening the file is the same as yours. Although it is read-only at the beginning on the client, it can still be edited after clicking Edit Presentation. This should be due to the permission setting of SharePoint not being synchronized to the Office client.
There is a workaround for your reference:
Directly create a PowerPoint Template file in the Office client, set it to read-only, and then upload it to SharePoint. In this way, no matter where you open the file, it cannot be edited.
The specific steps are as follows:
- Create a new PPT file and click Save-->more options to enter the following interface:
- Click more options on the page, click the drop-down button of Tool on the new page, and select General Options.
- In the pop-up window of General Options, set a password in the File sharing settings for this document section, and then click OK.
- Finally, upload it to SharePoint.
- Then, when you open the file on the client, the following prompt will appear:
Hope this helps.
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