Re: No exit sound on NVDA 2020.2 when I shut down my computer
Luke's suggestions are excellent. Remember, too, that an upgrade to NVDA involves an uninstall of the existing NVDA and install of the new one, so even that can change the position of NVDA in the shutdown process.
In addition to Luke's recommendations, if you (any you who's reading) do not have the Add-On Updater add-on installed, I'd suggest doing so. It is now configured such that it will detect when obsolete add-ons, such as Focus Highlight or Screen Curtain, are no longer needed when that functionality has been pulled into the NVDA core, and will remove them.
And as to searching the archives, which is always a good idea if you suspect something has been discussed in the past, here are step-by-step instructions for downloading: Searching the NVDA Group Archive
Brian - Windows 10 Pro, 64-Bit, Version 1909, Build 18363
Science has become just another voice in the room; it has lost its platform. Now, you simply declare your own truth.
~ Dr. Paul A. Offit, in New York Times article, How Anti-Vaccine Sentiment Took Hold in the United States, September 23, 2019