Repository: youtube-dl
Issue: Can't connect to proxy (407 ERROR)
Labels: external-bugs

## Please follow the guide below

- You will be asked some questions and requested to provide some information, please read them **carefully** and answer honestly
- Put an `x` into all the boxes [ ] relevant to your *issue* (like that [x])
- Use *Preview* tab to see how your issue will actually look like

---

### Make sure you are using the *latest* version: run `youtube-dl --version` and ensure your version is *2016.12.12*. If it's not read [this FAQ entry](https://github.com/rg3/youtube-dl/blob/master/README.md#how-do-i-update-youtube-dl) and update. Issues with outdated version will be rejected.
- [√] I've **verified** and **I assure** that I'm running youtube-dl **2016.12.12**

### Before submitting an *issue* make sure you have:
- [√] At least skimmed through [README](https://github.com/rg3/youtube-dl/blob/master/README.md) and **most notably** [FAQ](https://github.com/rg3/youtube-dl#faq) and [BUGS](https://github.com/rg3/youtube-dl#bugs) sections
- [√] [Searched](https://github.com/rg3/youtube-dl/search?type=Issues) the bugtracker for similar issues including closed ones

### What is the purpose of your *issue*?
- [ ] Bug report (encountered problems with youtube-dl)
- [ ] Site support request (request for adding support for a new site)
- [ ] Feature request (request for a new functionality)
- [√] Question
- [ ] Other

---

### The following sections concretize particular purposed issues, you can erase any section (the contents between triple ---) not applicable to your *issue*

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### If the purpose of this *issue* is a *bug report*, *site support request* or you are not completely sure provide the full verbose output as follows:

Add `-v` flag to **your command line** you run youtube-dl with, copy the **whole** output and insert it here. It should look similar to one below (replace it with **your** log inserted between triple ```):
```
$ youtube-dl -v <your command line>
[debug] System config: []
[debug] User config: []
[debug] Command-line args: [u'-v', u'http://www.youtube.com/watch?v=BaW_jenozKcj']
[debug] Encodings: locale cp1251, fs mbcs, out cp866, pref cp1251
[debug] youtube-dl version 2016.12.12
[debug] Python version 2.7.11 - Windows-2003Server-5.2.3790-SP2
[debug] exe versions: ffmpeg N-75573-g1d0487f, ffprobe N-75573-g1d0487f, rtmpdump 2.4
[debug] Proxy map: {}
...
<end of log>
```

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### If the purpose of this *issue* is a *site support request* please provide all kinds of example URLs support for which should be included (replace following example URLs by **yours**):
- Single video: https://www.youtube.com/watch?v=BaW_jenozKc
- Single video: https://youtu.be/BaW_jenozKc
- Playlist: https://www.youtube.com/playlist?list=PL4lCao7KL_QFVb7Iudeipvc2BCavECqzc

---

I'm in windows.
I use a proxy server that requires a user-name and a password. I have set my systems proxy manually in IE.
And this was worked very well.
But these several days, youtube-dl always tells me that failed to connect the proxy.
And I check the proxy in IE, it works well.
I really don't know why the problem be happened.
If it is the Windows issue?
Because Win10 had a upgrade several days ago.
Thank you for all you can advise anything.
![yy 20161215202255](https://cloud.githubusercontent.com/assets/22773754/21224399/f8738cc8-c306-11e6-9ab7-d771753aa813.png)