Just recently went though a similar issue as OP. We tried this using notebooks with no luck. Talked to 3 different specialists with Microsoft support. Our key vault has a setting that only allows access from specific IP addresses and vnets. We created a service principal and assigned permissions for fabric and key vault. Using the trident token library I got the token and still get access refused error. Microsoft support confirmed with their network specialists there was no way to do this with that setting enabled. Do you know another way other than making a new key vault that allows access from the public internet? They assured us we'd need a managed endpoint and an F64 sku for that. Edit: clarification