Hmm, which package exactly are you using? For example, I downloaded volatility-2.1_rc3.zip and put it on a Windows 7 SP1 x64 with Python 2.7.3. Everything seems fine to me. Do you have more than once python version installed and is %PYTHON_SCRIPTS% pointing to the right place? 

C:\Users\Elliot\Desktop\volatility-2.1_rc3>python --version
Python 2.7.3

C:\Users\Elliot\Desktop\volatility-2.1_rc3>systeminfo | findstr OS
OS Name:                   Microsoft Windows 7 Professional
OS Version:                6.1.7601 Service Pack 1 Build 7601
OS Manufacturer:           Microsoft Corporation
OS Configuration:          Standalone Workstation
OS Build Type:             Multiprocessor Free
BIOS Version:              Phoenix Technologies LTD 6.00, 6/2/2011

C:\Users\Elliot\Desktop\volatility-2.1_rc3>python vol.py -h
Volatile Systems Volatility Framework 2.1_rc3
Usage: Volatility - A memory forensics analysis platform.

Options:
  -h, --help            list all available options and their default values.
                        Default values may be set in the configuration file
                        (/etc/volatilityrc)
  -d, --debug           Debug volatility
..........

*NOTE* I didn't need to run setup.py at all to just to use it on the system. However if you want to install it, that's cool too (see below):

C:\Users\Elliot\Desktop\volatility-2.1_rc3>python setup.py install
........
running install_scripts
creating C:\Python27\Scripts
copying build\scripts-2.7\vol.py -> C:\Python27\Scripts
running install_data
creating C:\Python27\contrib
creating C:\Python27\contrib\plugins
copying contrib\plugins\disablewarnings.py -> C:\Python27\contrib\plugins
copying contrib\plugins\enumfunc.py -> C:\Python27\contrib\plugins
copying contrib\plugins\example.py -> C:\Python27\contrib\plugins
copying contrib\plugins\pagecheck.py -> C:\Python27\contrib\plugins
copying contrib\plugins\psdispscan.py -> C:\Python27\contrib\plugins
copying contrib\plugins\scanprof.py -> C:\Python27\contrib\plugins
copying contrib\plugins\verinfo.py -> C:\Python27\contrib\plugins
creating C:\Python27\contrib\plugins\addrspaces
copying contrib\plugins\addrspaces\ewf-python.py -> C:\Python27\contrib\plugins\addrspaces
copying contrib\plugins\addrspaces\ewf.py -> C:\Python27\contrib\plugins\addrspaces
running install_egg_info
Writing C:\Python27\Lib\site-packages\volatility-2.1_rc3-py2.7.egg-info

C:\Users\Elliot\Desktop\volatility-2.1_rc3>python C:\Python27\Scripts\vol.py -h
Volatile Systems Volatility Framework 2.1_rc3
Usage: Volatility - A memory forensics analysis platform.

Options:
  -h, --help            list all available options and their default values.
                        Default values may be set in the configuration file
                        (/etc/volatilityrc)
  -d, --debug           Debug volatility
  --plugins=PLUGINS     Additional plugin directories to use (colon separated)
  --info                Print information about all registered objects
..........

On Fri, Jul 27, 2012 at 1:56 PM, Skippy VonDrake <skippyvondrake@gmail.com> wrote:
> Just tried the 2.1 RC3 version and got the errors below.
>
> Then did the 'python setup.py clean' command followed by repeating the
> install command 'python setup.py install'.
> Still no difference.  No errors produced during install.  Egg was
> built and copied.
>
> Using Win7 and Python 2.7.3.
>
> D:\Forensics>python %PYTHON_SCRIPTS%\vol.py -h
> Volatile Systems Volatility Framework 2.1_rc3
> *** Failed to import
> volatility.plugins.overlays.windows.win2k8_sp1_x86 (AttributeError:
> 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.win7_sp0_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import
> volatility.plugins.overlays.windows.win2k3_sp1_x86 (AttributeError:
> 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.vista_sp1_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.win7_sp1_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.vista_sp2_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.xp_sp3_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import
> volatility.plugins.overlays.windows.win2k3_sp0_x86 (AttributeError:
> 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.xp_sp2_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import volatility.plugins.overlays.windows.vista_sp0_x86
> (AttributeError: 'module' object has no attribute 'xpsp2_types')
> *** Failed to import
> volatility.plugins.overlays.windows.win2k3_sp2_x86 (AttributeError:
> 'module' object has no attribute 'xpsp2_types')
> *** Failed to import
> volatility.plugins.overlays.windows.win2k8_sp2_x86 (AttributeError:
> 'module' object has no attribute 'xpsp2_types')
> Usage: Volatility - A memory forensics analysis platform.
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