Python will not install on my Windows 7 (64-bit) OS.

I have repeatedly tried the install with variations (specifying an install directly vs. taking the default; running as admininstrator vs. not; with and without logging) and with multiple downloads python-3.4.1.msi, python-3.4.1.amd64.msi, and python-3.4.0.amd64.msi.  No matter what, it always fails with the same symptoms.

msiexec log file is attached.  There are a number of errors indicated on the log, but the one that's fatal seems to be this one:

MSI (s) (24:8C) [14:46:34:848]: Executing op: CustomActionSchedule(Action=UpdatePip,ActionType=3090,Source=F:\Shared.W7\Python34\python.exe,Target=-m ensurepip -U --default-pip,)
CustomAction UpdatePip returned actual error code 3 (note this may not be 100% accurate if translation happened inside sandbox)
MSI (s) (24:8C) [14:46:34:957]: Note: 1: 1722 2: UpdatePip 3: F:\Shared.W7\Python34\python.exe 4: -m ensurepip -U --default-pip 
MSI (s) (24:8C) [14:46:34:957]: Note: 1: 2262 2: Error 3: -2147287038 
Error 1722. There is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected. Contact your support personnel or package vendor.  Action UpdatePip, location: F:\Shared.W7\Python34\python.exe, command: -m ensurepip -U --default-pip 
MSI (s) (24:8C) [14:46:41:292]: Note: 1: 2262 2: Error 3: -2147287038 
MSI (s) (24:8C) [14:46:41:292]: Product: Python 3.4.1 -- Error 1722. There is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected. Contact your support personnel or package vendor.  Action UpdatePip, location: F:\Shared.W7\Python34\python.exe, command: -m ensurepip -U --default-pip 

Action ended 14:46:41: InstallFinalize. Return value 3.

The same text, "There is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected. Contact your support personnel or package vendor." appears in a message box at the point of failure.