How to update version of Python?

Question

I had Python2.6 on my Windows 7 and I just installed Python2.7. As a result I have "C:\Python26" and "C:\Python27".

My problem is that system still tries to use the old version. For example if I type Python --version I get "Python 2.6.4". Or, if I try to install "numpy" it find the old version and does not allow me to manually change it to the new version.

I tried to check system environment variables to find out if there is Python2.6 (to replace it by Python2.7) but I did not find anything like that.

Solution

You need to change Python path to the new version.

http://docs.python.org/using/windows.html#excursus-setting-environment-variables

Comments

[Roman]

I checked it. I have the environment variable called PYTHONPATH but it does not have values that refer to the old version of python.

[Roman]

Anyway, I set PYTHONPATH=C:\Python27. Then I close all terminals and start a new one, type python --version and still get "Python 2.6.4".

[gruszczy]

I don't have much experience with windows. Don't you have to restart the system for this change to take effect?

[Roman]

I solved the problem. I have realized that in windows there are "user variables" and "system variables". First I checked "user variables" and did not find anything related there. But in the "system variables" I had "path" that refereed to the old version of the python. I changed the value of this variable and the problem was solved. Thank you!

[Thomas K]

@Roman: PATH is for finding programs to run at the command line. PYTHONPATH is for finding modules for Python to import.