Please confirm you are running version 126.96.36.19947 prior to installing this Patch 1. You can check this under Windows > Programs and features. After upgrading, your build will be version 188.8.131.5203.
Note: This patch needs to be installed only if you downloaded Veeam Availability Console 3.0 before April 23rd. Starting from this date, a new ISO image is available at Veeam.com that includes the patch.