ERROR: requested format not available

[israelbuitron]

youtube-dl -fc -v http://www.youtube.com/watch?v=aX8df2C7XoU
[debug] System config: []
[debug] User config: []
[debug] Command-line args: ['-fc', '-v', 'http://www.youtube.com/watch?v=aX8df2C7XoU']
[debug] youtube-dl version 2013.07.02
[debug] Python version 2.7.3 - Linux-3.2.0-49-generic-x86_64-with-Ubuntu-12.04-precise
[debug] Proxy map: {}
[youtube] Setting language
[youtube] aX8df2C7XoU: Downloading video webpage
[youtube] aX8df2C7XoU: Downloading video info webpage
[youtube] aX8df2C7XoU: Extracting video information
ERROR: requested format not available; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output.
Traceback (most recent call last):
  File "/usr/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 312, in extract_info
ie_result = ie.extract(url)
  File "/usr/bin/youtube-dl/youtube_dl/extractor/common.py", line 92, in extract
return self._real_extract(url)
  File "/usr/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 601, in _real_extract
raise ExtractorError(u'requested format not available')
ExtractorError: requested format not available; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output.

[jaimeMF]

The problem is that you have typed the options wrong, -fc is interpreted as if you want the format c which is not a valid format.
If you typed the c to turn on the option for resuming partially downloaded files, it's not necessary, it's the default behaviour.
For fixing the format option you have to specify a valid format code (use --list-formats to see the available for that video), for example -f 17.