Jenkins Agent instructions in UI tells user to run:

echo XXXXXXXX > secret-file

(where XXXXXXXX is a secret)

This is fine under Linux, but a little bit wrong under Windows. The space between last character of a secret and > sign is actually added into secret-file. Thus agent authentication doesn't work if one tries to use that secret file.

For it to work under Windows the command should be:

echo XXXXXXXX> secret-file