After Searching I found that the problem is : add-on SDK in incompatible with python 2.7.6 so that you have to use python 2.6.6 and to handle this error while using python 2.6.6
(c:\addon-sdk-1.15) C:\Users\Khaled\my-addon>cfx run
Traceback (most recent call last):
File "c:\addon-sdk-1.15\bin\cfx", line 33, in <module>
cuddlefish.run()
File "c:\addon-sdk-1.15\python-lib\cuddlefish\__init__.py", line 945, in run
pkgdir=options.pkgdir)
File "c:\addon-sdk-1.15\python-lib\cuddlefish\runner.py", line 639, in run_app
print >>sys.stderr, "Using binary at '%s'." % runner.binary
LookupError: unknown encoding: cp720
Error in atexit._run_exitfuncs:
Traceback (most recent call last):
File "C:\Python26\lib\atexit.py", line 24, in _run_exitfuncs
func(*targs, **kargs)
File "c:\addon-sdk-1.15\python-lib\cuddlefish\runner.py", line 533, in maybe_r
emove_outfile
os.remove(outfile)
WindowsError: [Error 32] The process cannot access the file because it is being
used by another process: 'c:\\users\\khaled\\appdata\\local\\temp\\harness-stdou
t-ecam39'
Error in sys.exitfunc:
Traceback (most recent call last):
File "C:\Python26\lib\atexit.py", line 24, in _run_exitfuncs
func(*targs, **kargs)
File "c:\addon-sdk-1.15\python-lib\cuddlefish\runner.py", line 533, in maybe_r
emove_outfile
os.remove(outfile)
WindowsError: [Error 32] The process cannot access the file because it is being
used by another process: 'c:\\users\\khaled\\appdata\\local\\temp\\harness-stdou
t-ecam39'
The Solution:
1- Download cp720
2- unzip the zip file.
3- Copy or Move the file cp720.py into your python encodings folder.
Example: C:\Python26\Lib\encodings\