I fixed the problem guys! The problem is that the Nexus Mod Manager has become a hidden or read only file. To fix this go to Computer/LocalDisk C/Users/Username/AppData/Local In the local file find the Black_Tree_Gaming folder.Right click on the folder and click properties and uncheck read only and hidden then click apply. Have it applied to all files. There ya go!
Note: if you cant find any of the files they may be hidden. To fix this, go to Control Panel / Appearance and Personalization / Folder Options / View then click the show hidden files and apply.