This is a numeric code returned when license file verification fails, reported in the hwGtlLicenseVerifyFailed notification, where 1 means an ESN/version mismatch, 2 an expired file, 3 a product type mismatch, and 4 an invalid file. An admin uses this code to quickly diagnose why a license upload was rejected without re-examining the file manually. For example, receiving code 3 tells the admin the license file was generated for a different hardware model than the one it's being applied to.