How to fix Python IMAP 'command CLOSE illegal in state AUTH, only allowed in states SELECTED

Problem:

You have IMAP code in Python similar to

server = imaplib.IMAP4_SSL('imap.mydomain.com')
server.login('[email protected]', 'password')
# ...
# Cleanup
server.close()

but when you run it, server.close() fails with an error message like

Traceback (most recent call last):
  File "./imaptest.py", line 13, in <module>
    server.close()
  File "/usr/lib/python3.6/imaplib.py", line 461, in close
    typ, dat = self._simple_command('CLOSE')
  File "/usr/lib/python3.6/imaplib.py", line 1196, in _simple_command
    return self._command_complete(name, self._command(name, *args))
  File "/usr/lib/python3.6/imaplib.py", line 944, in _command
    ', '.join(Commands[name])))
imaplib.error: command CLOSE illegal in state AUTH, only allowed in states SELECTED

Solution

Prior to server.close(), you must run server.select() at least once. If in doubt, just server.select("INBOX")because this will always work.

Insert this line before server.close():

server.select("INBOX")

It should look like this:

server = imaplib.IMAP4_SSL('imap.mydomain.com')
server.login('[email protected]', 'password')
# ...
# Cleanup
server.select("INBOX")
server.close()

For a complete example see Minimal Python IMAP over SSL example