Problem
When you try to use nano not as root user, this message pops up:

.nano_history: Permission denied

You can acknowledge it and move on. However, it is annoying.

Solution

sudo nano /etc/nanorc

Find the lines below and put a hash mark (#) in from of line “set historylog”. This should solve the problem.

## Enable ~/.nano_history for saving and reading search/replace strings.
#set historylog