@Paul: As the past tense of the verb, it would be logged in, as in I logged in this morning. As an adjectival phrase, it could be either logged in or logged-in, typically depending on placement, e.g.

Jul 12, 2019 · The user has been logged into the application and the ones that haven't. As the logged-in users always have a session on the application, I considered choosing sessioner.

It would seem from your description of COCA's usages that they use "to log in" when their prepositional phrase is not about what is being logged into but about something else since "to …

Jun 11, 2015 · Access -- What can this user do? A user who has access is an authorized user, or inversely and unauthorized user. In this case what you have is either a "logged in" user who is …

Apr 21, 2016 · The person was logged in to the website. log in is a phrasal verb so only the first part of the verb changes when you wish to change the tense. It follows the same rule as sit …

Dec 3, 2014 · If they are, they may be nouns instead of verbs (referring to the action of logging in or the state of being logged in). There is no widely-understood difference between any of …

Jan 31, 2017 · There are a lot of questions concerning the correct use if login, log in, etc. When speaking directly to an use I would say You can always change this permission by logging in in …

Apr 13, 2016 · A distinction can be made between 'not logged in' and 'logged out', in that 'logged out' may imply that the system has a record of a previous session where the user was logged in.

Dec 1, 2015 · For my money, log on to a system or log in to a system are interchangeable, and depend on the metaphor you are using (see comment on your post). I suppose there is a small …

They seem to be synonymous and from my experience they definitely are. In computer security, a login or logon (also called logging in or on and signing in or on) is the process by which …