What do mean with “I extracted files in newly formatted Ext4”? There are two ways of preparing an SD card for our ARM platforms:
1.) Download the *.tar.xz file (the root fs tarball) and make-sdcard (the setup script). The script will partition your card, copy the files and – depending on the platform – write boot record(s) that may reside outside the regular file area.
2.) Download the *.img.xz file (the root fs image), extract it (xz or 7zip) an use either dd (on Linux) or Win32DiskImager (on Windows) to dump it to the card.
None of the described methods requires the card to be formatted with any particular file system or even to be partitioned before. Note that in the second case, the root file system will automatically resize itself when booted for the first time. This step is not neccessary in the first case.
BTW, recent versions of make-sdcard allow to specify the URL of a *.tar.xz directly. So if you know your internet connection is good and you have curl installed on your system you can do something like: