Hi @john john Pter,
Thanks for reaching out to us. We are very pleased to assist you.
You disable file downloads by disabling the Open items permission which is a good way to do it.
The Open Items permission in SharePoint allows users to view the source of documents using server-side file handlers. This means that users can access the underlying content of documents, such as viewing the HTML source of a web page or the XML content of a document, without downloading the file itself.
We can read the content of the document normally, but with the following effects:
Restricted access to document content: Users are unable to view the internal structure or metadata of the document.
Limited Troubleshooting: This may prevent users who need to examine the content of a document for troubleshooting or validation purposes.
Enhanced Security: This enhances security by preventing users from accessing sensitive information embedded in documents.
If your documents do not contain any of the above affected sections, then you can use your own custom permission levels.
Also, for your "Read without download" permission level, SharePoint has a built-in Restricted Read permission level, which is based on Read to remove the download permission, you can also use this permission.
If you have any questions, please do not hesitate to contact me.
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