Can Otto use my Apple Mail? No - here's what to connect instead

You are on a Mac, your mail arrives in Apple Mail, and the app pointed you at a card that looked exactly right. In the words of the performer whose ticket produced this article: "It told me to add an email account and choose Mail App on this computer." You did that, and the test came back with "Found a mail app for my address, but Booked Solid cannot read it yet. Choose IMAP and use a provider-issued app password for background inbox listening." So you looked at the app password, decided that "using an app password made my security lower", went back to the Microsoft sign-in instead, and were sent round to the same card again. He wrote "This takes me back to 5 hours ago when this frustrating loop began" and then asked the only sensible question left: "Can't we just get Apple Mail App on here?" Here is the straight answer, and the way out.

The short answer: no, Otto cannot read Apple Mail

Booked Solid cannot read messages out of the Apple Mail app on your Mac. Not with a permission, not with a setting, not in any version you can install today. Thunderbird is the same story. If a card, a help screen, or the in-app Help buddy left you with the impression that Mail app on this computer will read Apple Mail, that impression is wrong, and chasing it is what creates the loop.

That is not the end of your setup, though, because of one thing worth understanding before you touch anything: Otto reads a mailbox, not the program you happen to read that mailbox in. Apple Mail is a window onto mail that actually lives somewhere else - Microsoft 365, iCloud, Gmail, or a web host. Connect Booked Solid to the mailbox at its source and you are reading the very same messages, while Apple Mail carries on exactly as it does now, untouched, on your Mac.

Why "Mail App on this computer" is a dead end

The in-app Help buddy is what sent this performer to that card, so if you landed there too, you were not being careless. It is still a dead end. The Mail app on this computer method has no working reader behind it in this version. All it does is look for Apple Mail or Thunderbird on your computer and, if it finds one, tell you it cannot read it.

There is a separate method just above it in the same list called Outlook app on this computer. That is the only local option that actually reads a mail program on your machine, and it reads the Outlook desktop program and nothing else. It is no help if your mail is in Apple Mail either.

Two different messages come out of it, and both mean stop:

• "Found a mail app for my address, but Booked Solid cannot read it yet. Choose IMAP and use a provider-issued app password for background inbox listening." This is what you get when the app can see that Apple Mail or Thunderbird is installed. Seeing it is not progress. It is the app telling you honestly that it found a mail program it cannot read.
• "No supported local mail reader is built yet. Choose IMAP and use a provider-issued app password." Same conclusion, shown when no mail program was detected at all.

The reason this feels like a trap is that the message names IMAP and an app password as the way forward, which is correct advice for some mailboxes and the wrong turn for others. Which one you are depends entirely on where your mail actually lives, so settle that first.

Step 1: work out where your mailbox really lives

• A work, school, or business address on Microsoft 365, or an Outlook.com address. Use the Microsoft 365 sign-in below. No app password, and nothing about your security changes.
• An iCloud address (@icloud.com, @me.com, or your own domain hosted at iCloud). Use Any email (IMAP) with an Apple app-specific password.
• A Gmail or Google Workspace address. Use Any email (IMAP) with a Google App Password. The full walkthrough is in Connect your Gmail with an app password (step by step).
• Anything else - a web host, a registrar, Fastmail, your own domain. Use Any email (IMAP) with whatever app password that provider issues.

If you genuinely are not sure, open Apple Mail and look at the account's incoming server. A server ending in outlook.com or office365.com means Microsoft's cloud. imap.mail.me.com means iCloud. imap.gmail.com means Google.

If your mailbox lives in Microsoft's cloud: sign in with a short code

This is the path that ends the loop, and it is worth being clear about why. It signs you in on Microsoft's own page with a short code, the standard device-code flow. No password is ever typed into Booked Solid, no app password is issued, and no security setting on your Microsoft account is loosened. It reads your mailbox straight from Microsoft's cloud, which means Apple Mail on your Mac is not involved and does not need to be running.

1. Open the Connections tab and scroll past Mail & calendars down to Tool access (optional).
2. Find the card Microsoft 365 (Outlook, Teams) and open it.
3. Click Sign in to Microsoft. The card shows you a short code.
4. On any device, go to microsoft.com/devicelogin, type that code, and sign in with that Microsoft account. There is nothing to paste back into Booked Solid - the card watches in the background and flips on its own.
5. The card turns green and reads Signed in as your address. If Microsoft signed you in without ever showing you a list of permissions to approve, that is normal on many tenants and is not a failure. The green line is what tells you it worked.
6. Click Turn on, right next to that green line. This is the step people miss. Signing in is not the same as switching it on, and until you tap it Otto is not reading anything.

The status note next to the green line says can save Outlook drafts. That wording trips people up: it does not mean you need the Outlook desktop program. It means any draft Otto prepares lands in that mailbox's own Drafts folder up in the cloud, which you can then open and send from Apple Mail, from your phone, or from Outlook on the web. Sending always stays with you.

There is more on what this connection can and cannot reach in Microsoft 365 by device code: what Otto can and cannot do in Outlook and in Connect Outlook and desktop mail (Microsoft 365).

Do not use IMAP for a Microsoft mailbox

You were right to push back. For a Microsoft 365 mailbox, the Any email (IMAP) route needs a legacy app password, and Microsoft makes you loosen account security to allow it. That really does lower your security, and nobody at Kivi Media will tell you otherwise. The device-code sign-in above exists precisely so you never have to.

If your mailbox lives at iCloud, Gmail, or a web host: IMAP with an app-specific password

For these providers an app-specific password is the safe path, not the risky one, and it is the method the providers themselves recommend. It is a separate password issued to one app only, it can be revoked on its own, and your real account password never enters Booked Solid.

1. Generate the app-specific password at your provider. For iCloud, that is account.apple.com under Sign-In and Security. For Gmail, it is myaccount.google.com/apppasswords, which only appears once 2-Step Verification is switched on.
2. In Booked Solid, open the Connections tab, go to Mail & calendars, and click Add an email account.
3. Leave the method on Any email (IMAP), which is the default. Do not change it to Mail app on this computer.
4. Give the account a name, pick its purpose tag, enter the address and server, and paste the app-specific password.
5. Click Save. The account then appears in your list of email accounts with a Check it button beside it. Tap that to test it.

Every error the Check it test can return is decoded in Add any inbox by IMAP: app passwords and every "Check it" error explained.

Once it is connected, you should not be opening Microsoft 365 yourself

If your daily routine has become "open the app, then go and open Microsoft 365 to actually deal with the mail", something is off. With the connection live you ask Otto directly: what needs my attention? or draft a reply to the latest email. He reads the mailbox from the cloud and prepares the draft, and the draft is waiting in your Drafts folder, which Apple Mail already shows you.

One honest limit here. The Open button on an item in the Inbox opens that message where it really lives, so for a Microsoft mailbox it opens Outlook on the web in your browser. There is no setting today that makes it hand the message to Apple Mail instead. If that button is the laborious part of your day, you do not have to use it - work the item in Booked Solid and let the draft land in Drafts.

If the in-app Help buddy tells you to lower your security, stop

This needs saying plainly, because it is the thing that turned a ten-minute setup into five hours. The in-app Help buddy contradicted human support in this exact scenario: support said an app password on a Microsoft mailbox lowers your security, and moments later the Help buddy said legacy security was really not that bad. The founder called that a real defect rather than a difference of opinion, and the Help buddy's knowledge was corrected so that the app and support now say the same thing about mail setup.

The rule that came out of it: if the in-app Help buddy ever tells you to lower your account security, or advises an app password on a Microsoft mailbox, stop and open a ticket rather than following it.

Two other limits, so you can plan around them

• One Microsoft account at a time. The Microsoft 365 card holds a single Microsoft account. Signing a second one in replaces the first rather than adding to it, and there is no app-password-free way to run two Microsoft mailboxes side by side in this version. If you need two, open a ticket saying which two and what each is for - it is a fair ask and it gets logged as a feature request. Multiple IMAP inboxes, by contrast, are fine: add as many as you like, each with its own app password and purpose tag.
• Switching to Outlook on the Mac may not help. If you were considering installing Outlook so that the desktop route works, know that the newer Outlook for Mac does not let other applications read its inbox, so the local Outlook connection cannot read it. The Microsoft 365 cloud sign-in reads that same mailbox reliably and is the better answer on a Mac either way.

If it still does not work

Two things are worth checking before you write in. Did the Microsoft 365 card actually go green and did you tap Turn on afterwards? And is the connection still switched on, or did an earlier troubleshooting step switch it off? If the card shows a red line instead of going green, that usually means your organisation has switched off user consent and a tenant administrator has to approve access for you.

Beyond that, submit a ticket from this help center. Tell us the address you are connecting, where that mailbox lives, and the exact words on the card, and we will take it from there. If you have been going in circles for hours, say so - that thread gets read by a person, and a case exactly like it is the reason this article exists.