Has anyone received a data plane failed message before?

Yes, this happens, and I’ve seen it a few times when a Key Vault is behind a VNet or Private Endpoint.

Even if the vault is configured correctly, the data-plane connection fails per-user when something in the network path is blocking their access. Since your boss can open the vault and you cannot, the issue is almost always tied to one of these:

Your client IP is not allowed If the vault is using a Private Endpoint, you must be coming from a network that can actually reach that private IP. Your boss may be connected through the correct network or VPN, and you may not.

Your NSG or firewall path is blocking the private endpoint Even one missing NSG rule on your subnet will cause the exact “data plane failed” message, while others still work.

Your DNS resolution is not pointing to the private endpoint Key Vault behind a private endpoint requires the private DNS zone mapping vaultname.vault.azure.net → <private-endpoint-IP> If your device resolves it to the public endpoint instead, you will hit the error immediately. This is the most common cause when one user works and another user does not.

You are not routing traffic through the VNet If your boss is on a corporate VPN and you are not, only they will reach the private endpoint.

What to check on your machine:

• Run nslookup <yourkeyvault>.vault.azure.net Make sure the IP returned is the private one, not a public Microsoft IP.

• Confirm you are connected to the same VPN or network as your boss.

• Make sure your subnet’s NSG allows outbound traffic to the private endpoint.

• If your company uses custom DNS, make sure your device is using those DNS servers and not a local/home DNS.

If all of that checks out, the only remaining cause is a per-user network routing or DNS mismatch, which your admin can fix quickly.

This error is not a Key Vault permission issue. It is a network reachability issue.