System Python conflict between Anaconda and existing Python installation

Question

I've been going with a basic Python3.4 install that I've been installing many modules into for over the past month but have reached a point where pip is coming up short and I'm going to just install the full Anaconda on my system to go deeper into bokeh-server stuff.

I get a popup during the Windows 64bit installer (Anaconda3-2.3.0-Windows-x86_64.exe) saying

A version of Python 3.4 (64-bit) is already at C:\Python34\ We recommend that if you want Anaconda registered as your system Python, you unregister this Python first. If you really know this is what you want, click OK, otherwise click cancel to continue.

Didn't find much documentation on this subject, and I'm not really sure how to "unregister" that installation of Python apart from uninstalling it entirely from Windows which I imagine would accomplish such a thing. Is this basically telling me to check how my Python Launcher for Windows is setup after the Anaconda installation? I'm completely unfamiliar with this notion of python system registration? Is that just a round about warning about which python version takes precedence on the system path, or which installation holds the file associations?

Solution 1

Here is a link to a script that will unregister a Python installation (if you haven't come across it already). I personally have not dealt with anything like this. It seems like it should work, but you may have to tinker around with some of the paths in the script to get things to work. The links in @nightuser 's post will also probably fix the issue.

Why not just remove your version of Python? You could do a pip freeze > requirements.txt with your current Python and add them to Anaconda, or create an environment with Anaconda using those packages. Anaconda has greatly decreased the amount of time I spend setting things up.

Solution 2

The solution is simply to uninstall python (for example, run the original python installer and select the uninstall option). The python key in the windows registry will be removed (which is what unregister means in this context).