Lots of other threads about similar issues, but none that I could find where quite the same case as mine. So, here goes:
Things I did:
I had the same problem setting up virtualenvwrapper on ubuntu.
I had installed virtualenv, virtualenvwrapper using pip which installed these modules in the site package of python3.5. How did I find that out?
Open your terminal and type
$ pip --version
pip 9.0.1 from /home/clyton/.virtualenvs/test1/lib/python3.5/site-packages (python 3.5)
Then I checked the variable VIRTUALENVWRAPPER_PYTHON
whose value was
/usr/bin/python.
On your terminal and type
$ ls -l $VIRTUALENVWRAPPER_PYTHON
lrwxrwxrwx 1 root root 9 Dec 10 2015 **/usr/bin/python -> python2.7**
As you can see this variable is pointing to python2.7 and you may have installed virtualenv in a different python site package.
So to fix this problem, just add the below line in your bashrc
VIRTUALENVWRAPPER_PYTHON=/usr/bin/python3.5
NOTE: Set the above value to the python version with which virtualenv was installed. In my case it was python3.5 so I have set that value. How to find out the python version used to install virtualenv? Again type pip --version
in the terminal.
Then open a new shell session and try mkvirtualenv again. This time it should work.