python - pip with ArcGIS 10.1 -

i have pip installed python 2.7, provided arcgis desktop 10.1. while pip works, only works when i'm in c:\python27\arcgis10.1\scripts directory, it's located. when try call different directory, error:

c:\> pip failed create process.

interestingly, pep8 (also in c:\python27\arcgis10.1\scripts directory) works fine directory. seems path variable working.

what's happening? on windows 7, if makes difference.

edit: further clarify, installed pip myself. did not come arcpy. same goes pep8.

if memory serves ran when having more 1 python folder in path and/or wrong pythonhome variable. try opening cmd shell , ensuring path , pythonhome clear of competing python entries , run pip again.

set path=c:\python27\arcgis10.1\scripts set pythonhome=c:\python27\arcgis10.1 pip --version 

if fails try upgrading/replacing pip get-pip (might have delete pip.exe in python\scripts folder first).

if works need clean path python folder in it.

if there 1 python folder in windows\system32 python files python27.dll -- compare c:\python27\arcgis10.1. if there duplicate files different sizes and/or date stamps there's problem.

pro tip: use where command search path given executable file or dll:

c:\> python* d:\b\osgeo\bin\python.exe d:\b\osgeo\bin\python27.dll d:\b\osgeo\bin\pythonw.exe c:\windows\system32\python27.dll c:\windows\system32\python34.dll 

the above system ripe unexpected problems. python's don't match:

 directory of c:\windows\system32  30-jun-14  04:08 pm         3,009,536 python27.dll 18-may-14  10:45         4,047,872 python34.dll   directory of d:\b\osgeo\bin  06-apr-13  07:55 pm            26,624 python.exe 06-apr-13  07:55 pm         2,448,384 python27.dll 06-apr-13  07:55 pm            27,136 pythonw.exe