When registering the ATP appliance, you are asked to upload the license file. After selecting the file, you see:

Error uploading license

This indicates a communication issue when trying to upload the file to our licensing servers.

1. Verify that the ATP appliance has access to the licensing servers; the Cynic license server [https://licensing.dmas.symantec.com] and the Aztec server [https://register.brightmail.com] by using the 'status_check' command at the console.
2. If status_check indicates EDR fails to access one or more servers, check unencrypted tcp connectivity more closely using tcp_check -t [server] -p 443
3. If tcp_check shows errors, resolve before continuing.
4. If tcp_check -t shows no errors, use tcp_check -s [server] -p 443 to check for issues specific to encrypted tcp traffic.