FATAL ERROR: Disconnected: No supported authentication methods availableGithub’s help on this isn’t actually very good.  And the solution is really quite easy when you get it working.

1. You _DO_ want to use plink for ssh when you’re installing msysgit.
2. Putty’s public key that you have saved isn’t in the right format for pasting into github.
3. fire up puttygen again, but choose to LOAD AN EXISTING KEY
4. copy and paste from _there_ into github.

Do not try things like opening up your saved public key, removing the comment lines, and adding “ssh-rsa” to the front or things like that.  It won’t work.

If you get this of these, you’re doing it wrong:

• FATAL ERROR: Disconnected: No supported authentication methods available

Some of the other advice on the net is for problems where plink can’t talk to pageant.  To make sure that’s not the case, you need to try using plink directly to login to github.

C:\somewhere>"c:\Program Files\PuTTY\plink.exe" -v -agent git@github.com

Looking up host "github.com"
...
SNNNIIIIPPPP
...
Pageant is running. Requesting keys.
Pageant has 1 SSH-2 keys
Using username "git".
Trying Pageant key #0
Server refused public key
Disconnected: No supported authentication methods available
FATAL ERROR: Disconnected: No supported authentication methods available

If you see that pageant is running, and it has a key, but it isn’t working, that’s a SURE sign that you just haven’t been able to convert the putty key format into a suitable format for github.