For reproducing an issue with pip

Make sure python.exe and pip.exe are on PATH, checkout the repository to C:\temp, and run the following commands:

C:\temp>pip freeze

C:\temp>python .\setup.py bdist_wheel

C:\temp>SET PYTHONPATH=%CD%

C:\temp>pip freeze
mypack==1.0

C:\temp>pip uninstall mypack
Can't uninstall 'mypack'. No files were found to uninstall.

This assumes a clean install of Python. If you have packages installed globally, you will see them in both freeze commands.