error argument of type nonetype is not iterable

[VladimirChk]

Hi, guys!
Error argument of type nonetype is not iterable then I trying to download video from YouTube. I press Analyze button and I see that error.
Version latest

[oop7]

Could you please provide the log and the version number you are currently using?

[Norvand]

I have the same issue with 5.1.0 (windows ffmpeg portable) -
ytsage.log
ytsage_error.log

[abenbenisok]

‌I'm experiencing the same issue, 5.1.0 windows ffmpeg portable

[oop7]

Hello @Norvand and @abenbenisok,

Could you please provide the steps to reproduce this bug?

[Norvand]

Could you please provide the steps to reproduce this bug?

Just open YTSage, paste yt url, click "analyze", and after "Extracting info..." got "argument of type 'NoneType' is not iterable"

Traceback (most recent call last):

> File "C:\Users\User\Desktop\YTSage\lib\ytsage\gui\ytsage_gui_analysis.py", line 75, in run
    self._analyze_url_with_subprocess(url)
    │    │                            └ 'https://www.youtube.com/watch?v=DLzxrzFCyOs'
    │    └ <function AnalysisThread._analyze_url_with_subprocess at 0x000001D489F242C0>
    └ <ytsage.gui.ytsage_gui_analysis.AnalysisThread(0x1d48c78c630) at 0x000001D489F526C0>

  File "C:\Users\User\Desktop\YTSage\lib\ytsage\gui\ytsage_gui_analysis.py", line 134, in _analyze_url_with_subprocess
    if "Private video" in result.stderr or "Sign in" in result.stderr:
                          │      │                      │      └ None
                          │      │                      └ CompletedProcess(args=[WindowsPath('C:/Users/User/AppData/Local/YTSage/bin/yt-dlp.exe'), '--dump-single-json', '--flat-pla...
                          │      └ None
                          └ CompletedProcess(args=[WindowsPath('C:/Users/User/AppData/Local/YTSage/bin/yt-dlp.exe'), '--dump-single-json', '--flat-pla...

TypeError: argument of type 'NoneType' is not iterable
2026-05-27 12:56:15.786 | INFO     | ytsage.gui.ytsage_gui_main:closeEvent:1194 - Application closing...

I added debug lines _analyze_url_with_subprocess:

 logger.error(f"yt-dlp return code: {result.returncode}")
 logger.error(f"yt-dlp stderr (raw): {repr(result.stderr)}")
 logger.error(f"yt-dlp stdout (raw): {repr(result.stdout)}")

and got

2026-05-27 13:24:54.312 | ERROR    | ytsage.gui.ytsage_gui_analysis:_analyze_url_with_subprocess:137 - yt-dlp return code: 1
2026-05-27 13:24:54.313 | ERROR    | ytsage.gui.ytsage_gui_analysis:_analyze_url_with_subprocess:138 - yt-dlp stderr (raw): None
2026-05-27 13:24:54.313 | ERROR    | ytsage.gui.ytsage_gui_analysis:_analyze_url_with_subprocess:139 - yt-dlp stdout (raw): 'null\n'
2026-05-27 13:24:54.313 | ERROR    | ytsage.gui.ytsage_gui_analysis:_analyze_url_with_subprocess:145 - yt-dlp failed: None

Then I executed it manually -

C:\Users\User\AppData\Local\YTSage\bin>yt-dlp.exe --dump-single-json --flat-playlist --no-warnings "https://www.youtube.com/watch?v=DLzxrzFCyOs" --cookies-from-browser "vivaldi"
ERROR: Could not copy Chrome cookie database. See  https://github.com/yt-dlp/yt-dlp/issues/7271  for more info
ERROR: Could not copy Chrome cookie database. See  https://github.com/yt-dlp/yt-dlp/issues/7271  for more info

[Seryi3]

Yes, I also encountered this message on version 5.1.0. The following steps helped: installing Mozilla Firefox, logging into YouTube with my username, and changing the browser in the downloader from Chrome to Firefox. I think it would be a good idea to specify in this program that it's better to use Firefox for cookie extraction.