Hello Kevin,
This mark means that the Host's version is older than the Viewer's. In other words, it shows version mismatch between Viewer and Host.
Note: this doesn't necessarily mean that your Viewer is the newest version. In order to be sure that there is no version mismatch between Viewer and Host AND both are upgraded to the latest version, you should first update Viewer and then Host/Hosts.
Here is an update guide
https://www.remoteutilities.com/support/docs/updating-remote-utilities/