Why can't I get into my email?

Three checks, in this order:

• Try webmail from your phone on cellular data. Not office Wi-Fi, cellular. If webmail works, your mail is fine and the problem is your computer or your office network. If webmail also fails, it is your account or the service.
• Ask a colleague. If everyone is affected, stop troubleshooting and call us. If it is only you, it is your account or your device.
• Check whether you were prompted for a password recently. A sudden password prompt that you clicked through, or a multi factor request you did not expect, matters and is worth mentioning when you call.

Take that last one seriously. If you received a multi factor prompt you did not trigger, someone has your password and is trying to get in. Do not approve it, and tell us the same day. This is the single most common way a business email compromise starts, and the prompt is your warning.

Otherwise the mundane causes are an expired password, a device that needs reauthenticating after a policy change, or a mailbox that has filled up.