Stop downloads on unmanaged devices - conditional access

@Aran Billen,Thanks for posting in Q&A.

From your description, I know you want to set a block policy on downloads from SharePoint and OneDrive for unmanaged devices.

Based on my researching, we can create a conditional access policy to block downloading from SharePoint and OneDrive for unmanaged devices.

Here are some links with useful information you can refer.

https://video2.skills-academy.com/en-us/sharepoint/control-access-from-unmanaged-devices

https://www.petervanderwoude.nl/post/conditional-access-and-blocking-downloads/

Non-official, just for reference.

Hope above information can be helpful.

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