Putty.exe – “Couldn’t agree a key exchange algorithm”
I had this issue today, on a host that had recently had a software upgrade. Problem: A host to which I was connecting with SSH gave this error: “Couldn’t agree a key exchange algorithm (available: Curve25519-sha256@libssh.org, ECDH-sha2-nistp521, ECDH-sha2-nistp384, ECDH-sha2-nistp256)”. Solution: In my case I updated to a later release of Putty.exe and the issue was resolved. […]
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