Using a Google or Microsoft account instead of a password, and when a provider can start an account.
You can sign in to Cartenda with your Google or Microsoft account instead of a password. Use the button for either one on the sign-in page, or connect one to the account you already have.
On a computer you use alone, tick Remember me on the sign-in page before choosing the button, and you stay signed in there. Otherwise you're signed out once you've been away for a while, as with a password.
Choose Continue with Google or Continue with Microsoft on the sign-in or sign-up page. If there is no Cartenda account for your address yet, one is made for you, and your email address counts as confirmed because the provider has confirmed it.
There is one exception. If you have no account and a firm holds your address for a client, choosing either button on the sign-in page opens your record with that firm and makes no account. To start a firm of your own, use the same button on the sign-up page.
A provider has to vouch for the address itself. Google does for Google accounts. Microsoft does only for a work or school account whose organization has verified its email domain with Microsoft. A personal Microsoft account (Outlook.com, Hotmail or Live) never is. When the provider has not confirmed the address, no account is made. Create one with your email address and a password instead, then connect Microsoft as described below.
This is what stops somebody from putting your address on an account of their own and using it to get into Cartenda as you.
From then on, either way in works. An account the provider has not vouched for can still be connected here, because you have already proved the address is yours by signing in.
If there is already a Cartenda account for your address and you use the provider's button on the sign-in page, it is only joined to that account when both the provider and Cartenda have confirmed the address. Otherwise sign in with your password and connect it from Settings → Security.
On Settings → Profile, type the new address. With a password, you're asked for it before you save. Without one, because you signed up with Google or Microsoft, the page asks you to confirm it's you first: you sign in with your provider again, come back to the page, and save. It has to be a fresh sign-in: if the provider says you last signed in more than a few minutes ago, or doesn't say, Cartenda can't confirm it's you and asks you to use your password or a passkey instead. A personal Microsoft account never says when you last signed in. If you have no password or passkey, choose Email me a link instead on the same page. We email a link to the address you sign in with, and opening it in the same browser within 15 minutes confirms it's you. You can then set a password on Settings → Security so you aren't asked for a link again.
Saving a new address disconnects Google and Microsoft, removes your passkeys, turns off two-factor authentication and signs out every other browser on your account. They were set up for the old address, and nothing set up there should still open the account once it has moved. You stay signed in where you are. Confirm the new address from the email we send, then connect your provider, add your passkeys and turn two-factor authentication back on, on Settings → Security. Without a password, set one there too, or you'll need Forgot password to get back in after you sign out.
On Settings → Security, under Connected accounts, click Disconnect beside it and confirm. If it is your only way in, set a password first on the same page. Disconnecting signs out every other browser on your account, including any that signed in with that provider or were remembered, so an account you don't recognize loses its way in at once. The browser you're using stays signed in.
Still stuck? Write to hello@cartenda.com and a person will answer.