Files get bigger while copying

I was stupid enough to forget I deleted an old backup so I could make a new one. A few days after deleting it my Windows crashed.

Now I'm trying to create a backup trough Debian. I'm copying my 1TB drive to a 1,5TB drive, with the Windows directory tree (not as an image). But my 1TB doesn't fit on the 1,5TB. There are no other files on the 1,5TB disk. Both Drives are NTFS.

What is happening and how do I fix this?