Due to the problems encountered when editing with Vegas Edit 21, I uninstalled absolutely everything from Magix (versions 19, 20 and 21), cleaned the registries and all the traces left on the PC. I downloaded the last update from Vegas Edit 21, version 208, which I tried to reinstall and I have the unpleasant surprise to find that it won't let me install it. I tried several times, absolutely useless. The highlight is that I installed Vegas Edit 19 without problems. I am in progress with a project started with Vegas Pro21, whose delivery deadline is already delayed due to program failures. It is possible that there is incompatibility with the latest updates to Windows 11, maybe.
I want to thank the Magix team for their promptness, even if the first answer did not help me. I want to share with other users who encountered the same problem, the solution proposed later, which worked for me.
"To be sure that the software is completely removed from your computer, please go to the link below:
Microsoft Fix: https://support.microsoft.com/en-us/help/17588/fix-problems-that-block-programs-from-being-installed-or-removed "