I have no hope explaining my users why when they create an anonymous sharing link and then try to open it just to make sue it works (while being logged in a browser with their Office 365 business account) it just doesn't work. They then think it is not working in general and then go to use WeTransfer, Dropbox, because OneDrive "doesn't work". I know that anonymous links should be opened with some generic guest user, but it should be handled more gracefully. Lately it become worse as the browser will remember your first try to open such link and will still show errors even if you logout from your work account. Only clearing cookies helps in that case.