Hi @Gian666
In the Meraki Dashboard, Group policies supersede Layer 7 rules. What this means is that you can continue blocking the category "Social web and photo sharing" for users on your network. Blocking their access to WhatsApp and other services that fall into this category.
You can then create a Group Policy, and use it to allow access to WhatsApp, for a group of users you would specify. This would allow you to block WhatsApp and other Social web and photo-sharing services to all, except a group of users you specify.
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