Now, re-download the game from scratch and do the entire process all over again but instead, call you back up folder BG3 FRESH INSTALL BACKUP or something like that and since it's new without mods you don't have to worry about the mods part, just back up the fresh install.Then, ...
Download the latest version: http://www.nexusmods.com/skyrimspecialedition/mods/modmanager/ It's been a long but lovely road for Nexus Mod Manager. The knowledge we've gained from NMM will be instrumental during the development of our next platform... Until then, stay tuned and happy ...