Outlook shows me as available when I'm busy — how to stop double bookings
Free/busy status, all-day events, and unticked conflict calendars are why bookings land on top of your meetings. Here's the exact fix.
Short answer: Your booking tool reads Outlook's free/busy status, not the presence of an event. Events marked Free, all-day events, events on a secondary calendar you never selected, and declined-but-still-visible invitations all read as open time. Fix it by setting the event's Show As to Busy, adding every conflicting calendar as a "check for conflicts" source, and re-running sync.
Why it happens
Microsoft Graph exposes a showAs field on every event with values like free, tentative, busy, oof, and workingElsewhere. Any sane scheduler treats free as bookable — otherwise a lunch reminder would block a client call. Outlook defaults all-day events to Free, which is the single most common cause of surprise double bookings.
The second cause is calendar scope. Connecting your Microsoft account grants access to many calendars, but a booking tool only blocks on the ones you explicitly mark as conflict sources. A team calendar, a shared family calendar, or a second mailbox stays invisible until you tick it.
Fix it, step by step
- Open the event that should have blocked you and check Show As. Set it to Busy and save.
- For recurring blocks (focus time, commute, gym), change the series, not the occurrence.
- In IntoCal, go to Dashboard → Integrations → Microsoft Outlook and open the calendar list.
- Tick every calendar that holds real conflicts under "check for conflicts". Leave the write target as one calendar.
- Click Sync now and reload your public booking page in an incognito window to confirm the slot is gone.
- Add a buffer (10–15 min) and a minimum notice window so a late-added event can't be undercut by an instant booking.
If it still shows you as free
| Symptom | Cause | Fix |
|---|---|---|
| Only all-day events leak | Outlook defaults all-day to Free | Set Show As to Busy, or enable "treat all-day events as busy" |
| Nothing has synced for days | Refresh token expired or was revoked | Reconnect in Integrations; the banner on your dashboard flags this |
| Only the last two weeks block | Sync window shorter than your booking horizon | Shorten the booking horizon or force a backfill sync |
| Invitations you declined still show | "Keep declined meetings" is on in Outlook | Delete declined events or set them to Free deliberately |
| Conflicts on a second mailbox | Shared mailbox not granted at consent time | Reconnect and approve access to that mailbox |
Prevent it permanently
Set your Outlook default for new all-day events to Busy, keep exactly one calendar as the booking write target, and let IntoCal's daily sync health check catch expired tokens before your guests do — it emails you a reconnect link the morning a connection breaks, so a stale token never quietly becomes a double booking.
Frequently asked questions
Why does my booking tool ignore some Outlook events?
It reads the free/busy status, not the presence of an event. Anything marked Free — including Outlook's default for all-day events — is treated as open time.
Do all-day Outlook events block bookings?
Not by default. Outlook marks all-day events as Free, so you must set Show As to Busy or enable the option to treat all-day events as busy.
Can I block availability with more than one Outlook calendar?
Yes. Tick every calendar as a conflict source in Integrations while keeping a single calendar as the write target for new bookings.
Why did sync silently stop working?
The Microsoft refresh token expired or was revoked. IntoCal's daily health check flags the connection as expired and emails you a reconnect link.
Do declined meetings still block my calendar?
They can, if Outlook is set to keep declined meetings. Delete them or mark them Free deliberately.
How do I stop double bookings for good?
Default new all-day events to Busy, keep one write-target calendar, tick every conflict calendar, and add a buffer plus a minimum notice window.
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