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First, use the procedure in this article to create an SSH key:(Lantronix Knowledge Base article 1166).
If you are having problems loading the generated key into a Spider or Spider Duo here are a few tips:
Many telnet clients and/or operating systems change the single Linux/Unix nl character (ASCII 0x0A) at the end of each line to a cr lf (0x0D 0x0A) sequence when you copy and paste.
Try pasting the key file you copied into a text file, then open the text file with a hex editor. There are many of them available on the web, for instance HxD for Windows:
http://mh-nexus.de/en/hxd/
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