Documents tower · floor

How to share Outlook calendar, and why their address decides it

The button is easy to find. What is not obvious about how to share outlook calendar entries with somebody is that the same button produces two completely different things — and which one you get is settled by their email address rather than by anything you choose on the way through.

The route itself is short, and identical in every recent version. From the navigation pane choose Calendar; on the Home tab choose Share calendar, picking which calendar if you keep more than one; type the person into the address box; then — and this is the step people skip — open the drop-down list beside their name and choose the level of access before pressing Share. One limit is worth knowing before you start: you can share with more than one person, but Microsoft notes “you can only add one person at a time.”

That second paragraph is worth reading twice if you have ever set up a stand-in for a holiday. A delegate can act for you — Microsoft says they “can schedule and respond to meetings on your behalf” — but only on your main calendar. If your team’s work actually lives on a project calendar you created, a delegate cannot be pointed at it. An editor can. People spend an afternoon looking for a Delegate option that a secondary calendar does not offer, and the rule that says so lives in a support article rather than beside the menu.

Those four lines explain nearly every complaint about a shared calendar. Somebody moves a meeting, tells the other person, and the other person still sees the old slot — so one of them assumes the sharing is broken. Nothing is broken. Inside one organisation the change is there before the sentence finishes; across two, it is on a roughly three-hourly cycle; into Gmail it may not surface until the following day, because at that point your calendar is a subscription and, in Microsoft’s words, the timing belongs to the recipient’s service.

This is also the practical answer to a question that gets asked backwards. If the exact minute matters — a shift rota, an on-call handover, a room booking people act on — then a link into a personal Gmail account is the wrong instrument, and no setting on your side will make it faster. The fast version exists only where both ends are inside the same organisation. It is the same question that decides whether a scheduled message leaves on time: is a server doing this, or is it happening on somebody’s own machine when they happen to be looking?

There is one more thing worth knowing about what the other person actually receives, because it is not what most people picture. In the current arrangement Microsoft does not simply give them a window onto your calendar: “A new calendar is created in the recipient’s mailbox, and this calendar contains a copy of the owner’s calendar (starting one year prior to date of acceptance).” They read from their own copy and write back to yours. The one-year figure is the part to remember — a colleague who accepts today does not get an archive of everything you have ever done, and if somebody needs a meeting from three years ago, sharing the calendar is not how they will find it.

Which brings up the obvious objection: not wanting a colleague to see the dentist, the interview, the difficult afternoon. The setting that solves it is not a setting. Microsoft: “Calendar sharing isn’t limited to the default Calendar folder that’s created in all Outlook profiles. You can create additional calendar folders and choose which of those folders to share.” That is also, in practice, the answer to how to create a shared calendar in outlook: you make a second calendar and share that one instead of your own. A calendar called Project, shared with the three people on the project, gives them everything they need and nothing they do not — and it sidesteps the blunter alternative of granting free/busy only and leaving everyone guessing what the busy block is.

Finally, the step that is not yours. Sharing sends an invitation, and it does nothing until it is taken up: “The person you’re sharing a calendar with will receive an email invitation to share their calendar. Once they accept, they can add your calendar to their own view.” If your calendar has not appeared for them, the first thing to check is not your permissions — it is whether that invitation is still sitting unopened in their mailbox.

The floors below take it four ways: what happens inside your organisation, what happens outside it, what to do when a shared calendar will not update, and how to share less than all of it.

What this tower will not do

It will not tell you a setting exists that makes an external calendar update instantly. Microsoft publishes the timings, they belong to the receiving service, and pretending otherwise wastes an afternoon.

It will not treat a shared calendar as harmless by default. What leaves your account is a copy of a year of your life, and the floor above says how to share a smaller one instead.

And it will not send you to a third-party sync tool first. Where Microsoft documents a route that works, that is the route the floor gives. What holds instead is simple: the permission levels, the sync timings, the one-year copy and the mobile-phone test are quoted from Microsoft’s own documentation, listed below.