I would by lying if I said I have completely purged my own workplace of this particular error. I’m working on it, honest! The question is:
Do I use “login” or “log in”.
The answer is surprisingly simple. Or at least, if you work it out in practical terms, it is simple… I’m going to throw in some good ol’ fashioned grammer(sic) terminology as well:
Login
Use “login” when it is an adjective (there’s the grammar term). This means, quite simply, use it when you’re describing something. “What kind of page am I visiting? Oh, a login page!” Note: if you prefer logging ON instead of IN, the same rule applies. “What kind of credentials are these? Oh, they’re my logon credentials!”
Log in
Use “log in” when you using it as a verb (terminology, yay!); ie., you are talking about the action of logging in. Come to think of it, that’s not a bad jumping-off point. You would never say in one word, “I am loggingin”… it’s always “I am logging in.”. By the same token, you would tell someone that they need to “log in”. Note: as per above, you would also tell someone to “log on”.
Log in at your login page.
Log on with your logon credentials.
Pedantic? You bet!