If you see this message and you know that your installation of PuTTY
\e{has} connected to the same server before, it may have been
recently upgraded to SSH protocol version 2. SSH protocols 1 and 2
-use separate host keys, so when you first use SSH 2 with a server
-you have only used SSH 1 with before, you will see this message
+use separate host keys, so when you first use SSH-2 with a server
+you have only used SSH-1 with before, you will see this message
again. You should verify the correctness of the key as before.
See \k{gs-hostkey} for more information on host keys.
terminate immediately after giving this error.
However, this error can also occur when memory is not running out at
-all, because PuTTY receives data in the wrong format. In SSH 2 and
+all, because PuTTY receives data in the wrong format. In SSH-2 and
also in SFTP, the server sends the length of each message before the
message itself; so PuTTY will receive the length, try to allocate
space for the message, and then receive the rest of the message. If
ridiculous amount of memory, and will terminate with an \q{Out of
memory} error.
-This can happen in SSH 2, if PuTTY and the server have not enabled
+This can happen in SSH-2, if PuTTY and the server have not enabled
encryption in the same way (see \k{faq-outofmem} in the FAQ). Some
versions of OpenSSH have a known problem with this: see
\k{faq-openssh-bad-openssl}.
bug in PuTTY. Please report it to us, and include the exact text
from the error message box.
-\H{errors-key-wrong-format} \q{Unable to use this private key file},
+\H{errors-cant-load-key} \q{Unable to use this private key file},
\q{Couldn't load private key}, \q{Key is of wrong type}
+\cfg{winhelp-topic}{errors.cantloadkey}
+
Various forms of this error are printed in the PuTTY window, or
written to the PuTTY Event Log (see \k{using-eventlog}) when trying
public-key authentication, or given by Pageant when trying to load a
This error occurs when PuTTY decrypts an SSH packet and its checksum
is not correct. This probably means something has gone wrong in the
encryption or decryption process. It's difficult to tell from this
-error message whether the problem is in the client or in the server.
+error message whether the problem is in the client, in the server,
+or in between.
A known server problem which can cause this error is described in
\k{faq-openssh-bad-openssl} in the FAQ.
in the server, or in between.
If you get this error, one thing you could try would be to fiddle
-with the setting of \q{Miscomputes SSH2 encryption keys} on the Bugs
+with the setting of \q{Miscomputes SSH-2 encryption keys} on the Bugs
panel (see \k{config-ssh-bug-derivekey2}).
Another known server problem which can cause this error is described