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.