You probably have a mismatched versions of the installer and the Python. If you're using 32-bit Python, you need the 32-bit installer. If you're using 64-bit Python, you need a 64-bit installer. There is no 64-bit installer on this site. I suggest you install distribute (http://pypi.python.org/pypi/distribute) and then run the command
\Python27\Scripts\easy_install pyserial
That worked for me.
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You probably have a mismatched versions of the installer and the Python. If you're using 32-bit Python, you need the 32-bit installer. If you're using 64-bit Python, you need a 64-bit installer. There is no 64-bit installer on this site. I suggest you install distribute (http://pypi.python.org/pypi/distribute) and then run the command
\Python27\Scripts\easy_install pyserial
That worked for me.
yep see comment below, thanks to jaraco
"pip" is also an alternative or downloading the source archive and running "python setup.py install".
2.7 released