Can someone explain what I'm doing wrong?

[SAVVYSCLUTTER]

I posted the following in another thread:

I'm downloading from Channel 4 in Edge on Win10 in VirtualBox (Win7 host). I used WidevineProxy2 with the first CDM in https://forum.videohelp.com/threads/417425-Real-Device-L3-Cdms. First, I ran the N_m3u8DL-RE command from WidevineProxy2 followed by

.\mp4decrypt --key 00000000000000000000000012743272:80e6b93ac609c4d09 64b40b1f8080141 stream_2025-09-12_18-03-37.mkv countdown.mp4

, which created a 0 KB file. Next, I changed format=mkv to format=mp4 in the N_m3u8DL-RE command and ran mp4decrypt, which created a file the same size as the encrypted file. When I play it in WMP or VLC, it's scrambled.

Someone replied with 'keys is fine, no problem with decrypt video https://gofile.io/d/aXtQHO'. I asked how he did it but didn't get a reply. I want to learn so I can do it next time.

Edit: URL is https://www.channel4.com/programmes/countdown/on-demand/77001-112

[iamghost]

with widevineproxy2

[Attachment 88756 - Click to enlarge]

[SAVVYSCLUTTER]

with widevineproxy2

[Attachment 88756 - Click to enlarge]

Please explain what you're showing.

[iamghost]

that where you can get keys from this and also with cmd line to download video and decrypt.
they are on sticky thread

[Attachment 88757 - Click to enlarge]

[z1269925944]

Title: Countdown S2025E112

Manifest URL: http://ak.dash01.stream.c4assets.com/wvmod-stream/CH4_33_05_42_77001_112_1_175638865785369.mpd?c3.ri=14664156373649312630

Subtitle URL: https://subs.channel4.com/77001_112_1/999d026084583c12a21a0608138d9af1.vtt

Keys: 1ffb17c6f0b3dc1625b4f39007219633:c3f340410e04de71e020b7339c2af922

Try this