Free unofficial windows software for windows

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WASTE will allow encrypted instant messaging, group chats and file-sharing and its published with complete source code.
WASTE is a software product and protocol that enables secure distributed communication for small (on the order of 10-50 nodes) trusted groups of users.
WASTE is designed to enable small companies and small teams within larger companies to easily communicate and collaborate in a secure and efficient fashion, independent of physical network topology.
Guide to Installing WASTE on Windows:
Download the WASTE installer from above.
Run the installer. Select whatever directory you choose to install to.
When prompted to move the mouse around to generate randomness, move the mouse around until the progress bar is full.
The WASTE Profile Setup Wizard should appear. Enter a nickname which you want to be known as on the network.
Select your approximate internet connection speed, then hit Next.
Click Run key generator... which
will allow you to generate a key pair for use with WASTE.
Enter a password to encrypt your private key with. This will prevent someone who gains access to your computer from stealing your private key. The password should be good and hard to guess. Then hit Generate.
At this time you should move your mouse around in the WASTE Key Generator Window a ton in order to generate lots of randomness. You will know you have done enough when the window says "Generating key pair...". When the generation is complete, WASTE will give you a message box telling you how long it took to generate the key. Hit OK.
At this point you should copy your public key to the clipboard using the button labeled "Copy my public key to the clipboard" and then paste it into an email/IM/whatever to give it to the person(s) you wish to connect to.
You should also acquire the public key of the person(s) you wish to connect to via some means, and then click the "Import public keys..." button in order to import their keys. Once you import their keys, there should be a message in the setup wizard telling you how many keys are loaded total.
Hit Next.
(Optionally) select a path to save new files in, and path(s) to allow people access to.
Hit Run.
WASTE should open with two windows, a main "buddy-list" type window, and a "Network Status" window. Go to the text entry field at the top of the network status box, and type in the host name of the person you wish to connect to. If when you hit enter something appears for a quick flash in the host list, and then disappears, it probably means that you dont have eachothers public keys. To doublecheck what keys you have, hit Ctrl+P to go to the preferences, then go to Ne twork/Public Keys tab.
To browse the network, hit Alt+B to open the browser, then click the upper left icon in the browser window to refresh. You can also type in search terms in to the browser address at the top to search.