Load key "/cygdrive/c/**/.ssh/id_rsa": invalid format

[Cyl18]

file format: key file type is ED25519, and I can use the key file from windows's ssh (e.g. from powershell: ssh [email protected])

[rhyst]

I had this issue and I replaced all the windows line endings \n\r with just linux line endings \n and it then worked

[keldian]

Add a single line feed (i.e. press Enter) at the end of the file.