I had this problem as it was downloading on a laptop partition without enough space on the smallest partition. In the C: drive there is a folder called "Windows10Upgrade" with a file called "Configuration.ini". Inside this file is the path to where it will copy the download. That particular line in the file was:
DownloadESDFolder=E:\\Windows10Upgrade\
which was a small partition for a Lenovo recovery utility. I switched it to:
DownloadESDFolder=C:\\Windows10Upgrade\image\
which allowed the file to download completely. You might be able to move the partially downloaded file over to that newly created image directory but I didn't think of this solution until after I had already deleted the file.
Hope this helps someone.
DownloadESDFolder=E:\\Windows10Upgrade\
which was a small partition for a Lenovo recovery utility. I switched it to:
DownloadESDFolder=C:\\Windows10Upgrade\image\
which allowed the file to download completely. You might be able to move the partially downloaded file over to that newly created image directory but I didn't think of this solution until after I had already deleted the file.
Hope this helps someone.