In computers based on a Debian operating system that uses Linux kernel, error messages similar to NO_PUBKEY may appear. This happens while using the Apt-Get command line tool, and this error is associated with the tool's update feature. This problem can be solved by simply keying in the appropriate commands.
Simply type the following commands, taking care to replace the number below with that of the key that was displayed in the error message:
gpg --keyserver pgpkeys.mit.edu --recv-key 010908312D230C5F
gpg -a --export 010908312D230C5F | sudo apt-key add -
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