When you head here and select ‘advanced options’, you have the ability to repair or reset the MSFS program settings. Doing so, it basically rebuilds the CFG file and clears all the packages-folders as to reinstall them during the next start up. I suppose some addons just don’t get updated in time and/or files are just redundant over time and this way in runs the most efficient again. It’s like a reinstall light, but this one only takes 5 seconds.
