That's actually the output from your shell. Since ampersand is one of the special shell characters it's interpreted by shell preventing you from passing the whole URL to youtube-dl. To disable your shell from interpreting the ampersands (or any other special characters) you have to either put the whole URL in quotes or escape them with a backslash (which approach will work depends on your shell).
-For example if your URL is https://www.youtube.com/watch?t=48&v=e2CXaJv0cMw you should end up with following command:
+For example if your URL is https://www.youtube.com/watch?t=4&v=BaW_jenozKc you should end up with following command:
-```youtube-dl 'https://www.youtube.com/watch?t=48&v=e2CXaJv0cMw'```
+```youtube-dl 'https://www.youtube.com/watch?t=4&v=BaW_jenozKc'```
or
-```youtube-dl https://www.youtube.com/watch?t=48\&v=e2CXaJv0cMw```
+```youtube-dl https://www.youtube.com/watch?t=4\&v=BaW_jenozKc```
For Windows you have to use the double quotes:
-```youtube-dl "https://www.youtube.com/watch?t=48&v=e2CXaJv0cMw"```
+```youtube-dl "https://www.youtube.com/watch?t=4&v=BaW_jenozKc"```
### ExtractorError: Could not find JS function u'OF'