Unable to copy files previously extracted from archives created on a Mac, even after claiming ownership

Question

I reinstalled Windows on my computer today, and backed up my music to a USB drive. Now, I'm trying to copy the files onto my fresh Windows partition, but I'm unable to copy files that I obtained within my previous Windows installation from zip archives created on Macs.

When I try to copy those previously-extracted files, I get an error saying that I need permission from S-1-5-21-...-1000 (a bizarre long ID).

The first thing I tried was to take ownership of the files by setting my new user account as the owner, but that resulted in errors saying that I need permission from myself!

Some Googling suggested adding antivirus suggestions, so I excluded the relevant folders from Microsoft Security Essentials, but the issue persists.

For what it's worth, it seems that some program (so far I've only installed Chrome, Microsoft Security Essentials, and the latest Windows updates) created an empty folder named 601c8c7f0e0c03f725 at the root of my external USB hard drive.

Also, these files are simply mp3's, with no DRM protection.

What gives?

Answer 1

S-1-5-21-...-1000 is a user account SID from the old OS.

put all the extracted files in one folder and run these 2 commands one at a time using an elevated command prompt, hit enter after each command, be sure spaces are in the correct place also.

takeown /f [path to folder] /r /d y

then

icacls [path to folder] /grant administrators:F /T

if the folder with extracted files is named "backup" on the root of the C drive, then [path to folder] would be replaced with C:\backup without brackets