Originally Posted by mony
yes i did and saying connection refused
and what or where is yes at security alert
Did you try to connect as SSH (not telnet)? If you did, and if the kindle was running SSH, then PuTTY should have asked (one time) if you want to allow using a new SSL key in a "security alert" popup dialog box.
"Connection refused" indicates that SSH is (probably) not running in the kindle. If you installed the diags partition (and matching kernel) with SSH, the N U Z X menu selection SHOULD start SSH.
FYI: The "forensics" pastebin in the "simple debricking" sticky first post now contains a 5.1.0 main kernel, so you can now flash that with fastboot, then flash the 5.1.0 main partition from diags SSH. You can still flash 5.0.0 main kernel and partition if you want to use an older firmware version.