How to appcfg rollback my project?

Question

I am using Google App Engine to upload my python project However once I try to upload my project I receive this error:

2013-07-24 20:21:06 Running command: "['C:\\Python26\\python.exe', '-u', 'C:\\Program Files\\Google\\google_appengine\\appcfg.py', '--no_cookies', u'--email=[e-mail]', '--passin', 'update', 'C:\\Users\\Thomas Stone\\Documents\\proxy-server']"
08:21 PM Host: appengine.google.com
08:21 PM Application: mathsonlinegames; version: secureable
08:21 PM 
Starting update of app: mathsonlinegames, version: secureable
08:21 PM Getting current resource limits.
Password for [e-mail]: 08:21 PM Scanning files on local disk.
Error 409: --- begin server output ---
Another transaction by user Thomasston54321 is already in progress for app: s~mathsonlinegames, version: secureable. That user can undo the transaction with "appcfg rollback".
--- end server output ---
2013-07-24 20:21:16 (Process exited with code 1)

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Because of this I have tried this in CMD:

cd C:\Program Files\Google\google_appengine
appcfg.py rollback C:\Users\Thomas Stone\Documents\proxy-server

But then I receive this error in CMD

Usage: appcfg.py [options] rollback <directory> | <file>

appcfg.py: error: Expected a single <directory> or <file> argument.

Answer 1

Using Java Eclipse GAE, this worked for me.

C:\Program Files (x86)\Google\appengine-java-sdk-1.9.36\bin>appcfg --no_cookies --email=[e-mail] --passin rollback "C:\eclipse\workspace\project-id\war"

Answer 2

appcfg.py rollback ./

all you need...