I've OpenSSH 7.6 installed in Windows 7 for testing purposes. SSH client & server work just fine till I tried to access one of my AWS EC2 box from this windows. It seems like I need to change the permission on the private key file. This can be easily done on unix/linux with `chmod` command. What about windows? C:\>ssh -V OpenSSH_7.6p1, LibreSSL 2.5.3 C:\>ver Microsoft Windows [Version 6.1.7601] C:\> C:\>ssh [email protected] -i private-key.ppk @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: UNPROTECTED PRIVATE KEY FILE! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Permissions for 'private-key.ppk' are too open. It is required that your private key files are NOT accessible by others. This private key will be ignored. Load key "private-key.ppk": bad permissions [email protected]: Permission denied (publickey). C:\> C:\> C:\>ssh [email protected] -i private-key.ppm Warning: Identity file private-key.ppm not accessible: No such file or directory. [email protected]: Permission denied (publickey). C:\>