Im having a similar problem. . . a couple days ago download of a folder or multiple files stopped working.
the button to download is there but clicking it does nothing. no matter if its 2 files or a folder full of files. nothing.
also tried with different accounts. seems to be a problem with MS.
and worst of all there is no error message, or indication of what is going wrong or how to go about an alternative method. i need to download about 800 files in a grouped organized folder structure, i cant do this one by one, itll take me the whole day. please provide a work around.