What to do when you get “This file is not SDC file or the format is not supported” from Unpacksdc
Assume you are downloading Windows 7:
en_windows_7_professional_x86_dvd_x15-65804.01.sdc en_windows_7_professional_x86_dvd_x15-65804.02.sdc
The unpacksdc can’t handle it, so just copy paste them to the C:\Temp\ (or wherever you download the Windows 7)
And resume the download from exe, it will continue from %90, and it will be less painful

I got a similar experience . First I used the formal downloader from the e-Academy site. After finish downloading the file: en_windows_7_professional_x86_dvd_x15-65804.01.sdc, it starts unpacking, checking CRC passed, then unpacking hang at 1% for hours. I thought the downloader could not handle it. So I used unpacksdc, but it gives me the same message:
UnpackSDC 1.1 (c) imagi
This file is not SDC file or this format is not supported.
I am waiting any solution
I’m pretty much impressed with the stability of Windows 7. It is better than windows Vista which hogs my memory and cpu.*”.