If you've created an encrypted directory using EncFS, it's likely that at some point you'll want to change your password - this is a painless process using the command line.
From a terminal, type:
encfsctl passwd /path/rootdir
Where /path/rootdir is the path to the directory that stores the encrypted data (This is not the mount point directory - the root directory address will likely begin with a period - for example: /home/jogga/.rootdir).
You'll be prompted for your current password and then your new password. Once you have verified the new password successfully, you'll see the following confirmation message:
Volume Key successfully updated.
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