Signature extraction failed - python runtime error

[meain]

Signature extraction failed: Traceback (most recent call last):
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 817, in _decrypt_signature
video_id, player_url, s
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 744, in _extract_signature_function
cache_res = res(test_string)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 796, in
return lambda s: initial_function([s])
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 254, in resf
res, abort = self.interpret_statement(stmt, local_vars)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 55, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 135, in interpret_expression
self._objects[variable] = self.extract_object(variable)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 220, in extract_object
fields = obj_m.group('fields')
AttributeError: 'NoneType' object has no attribute 'group'
(caused by AttributeError("'NoneType' object has no attribute 'group'",));

[phihag]

Can you post the entire error output? The output should start with something along the lines of [debug] System config: []. Also make sure that you are using the latest version of youtube-dl.

[phihag]

I am closing this issue for now, because I strongly suspect that your version of youtube-dl is simply out of date. If that is not the case, please post the complete output and we will reopen this issue. Thanks!

[atropo]

I can confirm that upgrading to 2015.11.24 solved the issue for me.

[meain]

I had installed the latest version but still had the error, it is working after a restart. Don't know if it is the restart or not but it is working now.

The error was after : Downloading js player en_US-vflFEzfy7