Hi @mr_mahoney,
I do not believe this can be changed on the dashboard as the access point will use the User-Agent string field of an HTTP GET request packet to determine the operating system of the client when it first associates, and allow or deny access accordingly.
Some clients may misidentify themselves when specifying the User-Agent string field of an HTTP GET request.
Device type policy enforcement is done on a best-effort basis, dependent upon the information that the client provides. When needing to enforce security-focused policies based on device type, please leverage solutions such as Meraki Systems Manager, or Cisco ISE.
Please take a look at this KB for your reference.
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