You Do Not Have Permission to Download to A Null Folder

Hello. I'm trying to download a file through Safari. After I click 'Allow', I receive the message "You do not have permission to download to a Null Folder". How could I have a null folder? I've gone into Safari Settings and verified that downloaded files should go to my Downloads folder. Also, this is a brand new MacBook Air that I'm setting up today. Any help would be greatly appreciated.