Sentry admins may notice an error On the System-->Settings-->License page of the WebAdmin interface when attempting to obtain (lease) a license from a License Server, even when all fields are set correctly and licenses are available on the sever.
Invalid signature : Server returned HTTP response code: 401 for URL: https://license_server_hostname:5443/license/api/v1/leases
There are 2 common reasons for this error:
1. The time on the Sentry instance is off. This is the most common cause of the error. Check the time and time zone settings on your Sentry instance and try the lease again. The Sentry instances and the License Server should ideally be using the same NTP server for time syncing.
2. This Sentry instance version is not compatible with the License Server version. This is a rare issue. Contact Forum Support for assistance updating the License Server to the correct release for your Sentry instances.