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I have python 3.3 and 2.7 installed on my computer. Lately I decided to run python 2.7 more form Run, when previously python 3.3 was used. ("python" auto-completes in Run)

In order to do it, I changed the PATH system variable to C:\python27 from C:\python33.

When I run from CMD itself, python 2.7 opens. However, when I try to do it from Run, it doesn't work at all.

Any help? I am far more curios about the "why" rather then want a solution.

Notes: * I tried looking at HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\RunMRU, thinking about some sort of cache, but the paths there are of python27. * My user PATH variable is not relevant, I checked. * I tried removing python 2.7's path completely, however when I try running python, 3.3 opens.

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What happens if you log out and log back in? – Nicole Hamilton Feb 26 '13 at 20:23
Still the same. Python 3.3 runs. – Tapuzi Feb 26 '13 at 20:30
up vote 1 down vote accepted

Make sure you only have one python directory in your path varible. alternately, you can check HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths to see if you have a key for your python interpreter, and if not create a key indicating your executable. some more info here:

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That fixed it! thank you. Pretty cool. – Tapuzi Mar 1 '13 at 10:23

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