Currently on viewer 126.96.36.199 trying to push out a 188.8.131.52 MSI.
This looks like a version mismatch. The Viewer checks the Host's installer version against its own version before the update.
It is highly recommended that you first upgrade the Viewer to the most recent version (184.108.40.206) and then upgrade your Hosts to the same version. Having different versions of Viewer and Host can result in unpredictable behavior and issues hard to diagnose.