If Python is already in the environment variables, just do it like this:

python -m pip install -U nome_pacote

If not:

<pasta_onde_esta_instalado>\python.exe -m pip install -U nome_pacote

It is very likely that you have installed Python inside the Folder C:\Programs and Files or C:\Programs and Files (x64) (or another folder without write permission), that is, your user does not have permission to write in these folders, right after you think you have installed it is likely that something else has happened.

The ideal way to make it easier would be to install perhaps in the root, or in your user's folder, i.e. first you will have to remove Python and then Install again and change the installation location.

Other way to install, if that's what you want, is to install pip with elevated privileges

Run cmd as Windows 7 administrator

Open the Start menu and the in the search field type cmd, when it appears in the programs the cmd right-click / mouse and select Executar como administrador

Run cmd as administrator Windows 8 and 10

Note: in win8 probably works, in Win10 I do not know if this option appears in all, maybe it has been replaced by PowerShell

Right-click / mouse on the Start Menu and select the option prompt de comando (admin):

Windows 10 and PowerShell as administrator

Maybe your Win10 may not have the Command prompt in the menu items, but powershell is able to do the same as cmd (and more), so right click / mouse on the Start Menu and select the option Windows PowerShell (Admin):

Now download https://bootstrap.pypa.io/get-pip.py and then run and depending on where you downloaded use cd to navigate, example:

cd C:\Users\[Nome do seu usuário padrão]\Downloads

And then run it by typing this into the terminal:

python get-pip.py

Anyway if you can avoid Programs And Files or any folder that needs privileges, it will be better (easier).

I managed to update mine.

Goes into python files

C:\Users [user_name] \ AppData\Local\Programs \ Python\Python37\Scripts

And opens the pip files

Pip.exe

Pip3.7.exe

Pip3.exe

Enter cmd and Type

C:\users[user_name] \ appdata\local\programs \ python\python37\python.exe-m pip install --upgrade pip

When it updates it is already installed on the cmd

Hope I helped!good luck!

You need to create a file somewhere (it can be on your desktop) with the name get-pip.py and put the code that is in this link.

After saving the file, go to the file directory in your CMD and Type:

python get-pip.py

This will install pip on your computer.

I managed to solve as follows; Even my system being 64x seems to me that git does not run right. It features pip version 7.0 and UI updates neither the pau. I had to install python 86x to be able to run git and the rest of the packages I wanted as kivy. In this version it is with pip 9.0.

To install pip through a proxy.

Follow the instructions below.

Access: https://bootstrap.pypa.io/get-pip.py

Save the file get-pip.py in a folder and go to the file directory in your CMD and Type:

1. If your proxy is over http and authenticated:
   set http_proxy=usuario:senha@servidor:porta

2. If your proxy is over https and authenticated:
   set https_proxy=usuario:senha@servidor:porta

3. If your proxy is via http without authentication:
   set http_proxy=servidor:porta

4. If your proxy is over https without authentication:
   set https_proxy=servidor:porta

The server has to have the entire domain, for example, ending with ".com.br " or enter his IP.

Then just Type:
python get-pip.py

Remember that python needs to be in your windows variable PATH.

And a Scripts folder will be created inside your Python folder with pip.

To Me the same thing happened a day before that, I had to install pyinstaller, usually with the command pip, and after that, no problems, I did a conversion of a .py-when you try to do another conversion, on the day after, he said that the command pyInstaller (which is Responsible for the conversion were not available, so I went to try to re-install the PyInstaller via the command pip, and it is said that the pip was not there too, so I try to run it through the CMD command in python, to check to see if it was normal, and the it turned out that not even the "python" command was recognized, despite python being installed on my computer. My solution was to reinstall python, and after that install PyInstaller again.

Hope it helps you! Good luck!