So you want to ssh somewhere from a Windows machine. The first step is to install putty. But, no you can’t ssh because putty won’t use the pem file you’ve been given by some geek, nerd, gnome. A little Googling and now it’s time for puttygen. Following the directions, load plus all files plus pick your pem and error message!
This message has nothing to do with the key header and most likely is whitespace at the end of lines caused by Windows-to-Linux-to-MacOS-to-WhoKnowsWhat. Just open the pem in Notepad and make sure there is nothing at the end of the lines. Once you have deleted all of the invisible stuff, try the load again. Also remember to actually save the new ppk format cert with a ppk extension or you’ll be in putty-hell a bit longer trying to find a cert that is not there (C:\Users\your-account-here\Documents\auth\your-cert.ppk).
