Your viewing experience of the MusicMaster website, as well as the web as a whole, would be much improved if you upgraded your browser.
MusicMaster Blog
Support Bulletin: ESET Internet Security and MusicMaster posted on May 4th, 2022
It has come to our attention that the most recent release of ESET Internet Security (Version 15.1.12.0) can inadvertently cause MusicMaster Pro to terminate during the license check. This will result in an abrupt software failure.
If you have recently upgraded your ESET product and are having this problem, please contact your MusicMaster support rep for assistance. We are working with ESET to find a permanent solution to this incompatibility and will update this notice as new information becomes available.
Update: It appears that once the ESET protection is updated to May 10, 2022 or later, this problem no longer occurs.