Duplicati Error:  CryptographicException: Bad Data

Duplicati Error:

Connection Failed:  Session.connect:

CryptographicException: Bad Data.

The Fix:

1 – Download psftp from the web’ski:  http://tartarus.org/~simon/putty-snapshots/x86/psftp.exe
* BTW – that’s THE source for that file, download nowhere else!
2 – Drop that file in c:\windows\system32 (or syswow64 but sys32 works well)
3 – Open command prompt as the user doing the backup

cd \
cd windows\system32
psftp -P 1000 user@yourdomain.com

* The “-P 1000” is “port 1000”, put in your port number that you’re using here
* The “y” imports the cert into the registry

4 – Open Duplicati and select the option when typing in your username, path, etc to use an alternate sftp program.  When testing it will give you a warning that it will probably work if the program is in the system path because it can’t detect an sftp program.  It will indeed work.

On linux this isn’t an issue :P  Seems like on WindERS it’s a problem BUT using an alternate sftp program does let you use an alternate port!!!