Question: I am running Windows 7 and have Python 3.3 64 bit installed. I seem to have a problem importing the tkinter module, I can import it fine through the python IDLE and it will work, but when I save the .py file and double click it, a cmd window will open and say:

```
Traceback (most recent call last):
File "C:Users\username\Desktop\g.py", line 3, in <module>
from tkinter import *
ImportError: No module named tkinter

```

I have tried the following:

1. I have tried `import tkinter`, `from tkinter import *`, and `import tkinter as tk` and they don't seem to work when the `.py` file is opened directly (double clicked).
2. I also double checked the path variable and it was set correctly.
3. I uninstalled python and reinstalled it.
4. I checked to see if tkinter is in the folder C:\Python33\Lib\, and it is.
5. I do have a `mainloop()` in my program.
6. In my program, tkinter is all lowercase.
7. I tried a lot of solutions online from other posts, and they didn't work for me.

The top of my code is:

```
import sys

from tkinter import *

```

I don't know what I am missing, any suggestions?

Answer: 
I'm going to make this an answer then for anybody in the future.

The problem is that Windows is currently set to run all `.py` files with a different executable (probably a Python 2.x one) To fix the problem, follow these steps:

1. Right-click a `.py` file.
2. In the menu that pops up, go to `Open with`.
3. In the submenu that pops up, click on `Choose default program...`
4. A window will then appear. In this window, click on the `Browse...` button.
5. Then, go find the Python execuatble. It should be at `C:\Python33\python3.3.exe`. (There might be multiple `pythonX.exe` files. If one doesn't work, try another.)
6. Once you select it, click `Open`.

If done correctly, this procedure will manually reset the default executable for `.py` files to be the Python 3.x one. Meaning, your script should run fine now.
This is actually a simple solution.
You have:

```
    from tkinter import *

```

You need:

```
    from Tkinter import *

```

Capitalization is very specific!!!