Upload and download failure

It was working yesterday allegedly!  today, any uploaded file shows the following error messsage:


Upload complete, writing file(s)...

 
 File 'biggestloserpayouts.xls' could not be written

And any downloaded file is unable to open or shows "Downloader failed"

Any ideas?
 

  

Hi Keith,
It seems that NTFS permissions on your service folders or custom paths are somehow reset or changed, please check them.