A customer emails info@ on a Friday afternoon. Three people watch that inbox. By Monday morning, the customer has either two answers or none.
That is not a people problem. It is a setup problem, and it starts with what that address actually is.
Three kinds of address, three different outcomes
Most small businesses have an info@, an office@, a billing@, or a service@. Underneath, it is usually one of three things.
It is somebody's personal mailbox. Now the front door of the business belongs to one employee. When they take a week off, the business looks closed.
Or it is a distribution list. A list does one thing: it forwards a copy of every message to each person on it. Replies then come out of private mailboxes. Nobody can see who answered, or what they said, or when. The customer who writes back a second time lands in a different person's inbox than the first time.
Or it is a shared mailbox. That is the one Microsoft built for exactly this.
The shared mailbox you are already paying for
A shared mailbox is a single mailbox with a single address that several people open at once. Everybody sees the same inbox, the same folders, the same sent mail. You reply as info@, not as yourself.
Microsoft's documentation is specific about the rules. A shared mailbox can hold up to 50 GB without a license of its own. It is not meant for direct sign-in, so that account should stay blocked. Access is limited to people inside your organization, and it supports a maximum of 25 users. Each person who opens it still needs their own licensed mailbox. The mailbox is included in what you already buy. The people are not.
So if you are paying for Microsoft 365 and still running info@ through a distribution list or through one employee's inbox, you already own the better version.
The setting almost nobody turns on
Here is the part that causes real damage.
When you reply from a shared mailbox, that reply is saved in your own Sent Items folder, not in the shared mailbox. Microsoft documents this behavior directly, and it catches people off guard. The shared mailbox's Sent Items folder sits empty while the mailbox sends replies all day long.
So the next person who opens it sees an unanswered email. Two things happen. Sometimes two people answer the same customer. More often, everyone assumes someone else took it, and the customer waits.
The fix is one setting on the mailbox. In the admin center, under Teams and groups, open Shared mailboxes, pick the mailbox, find the Sent items section, and turn on the copy option. Whoever holds your admin account can check it in about a minute. For a support or billing address, that minute changes the whole picture.
Two quiet ways a shared mailbox stops working
The first is size. Microsoft warns that when a shared mailbox reaches its storage limit, it can still receive mail for a while but cannot send. After some time it stops receiving altogether, and senders start getting bounce messages. It fails on the customer's end first, which is the worst place for a business to learn about it. The mailbox usage report in the admin center shows how full each one is.
The second is the account behind it. When you convert a departing employee's mailbox into a shared one, do not delete that old account. Microsoft's instructions say plainly that the account anchors the shared mailbox. Delete it and the mailbox goes with it. Keep sign-in blocked on that account, and reset its password, because Microsoft notes the original username and password keep working on that mailbox after the conversion if nobody changes them. One more detail worth knowing: the convert option only appears while the mailbox still holds a license, so remove the license after the conversion, not before.
What to look at this week
You do not need to buy anything for any of this. You need to look.
Count the addresses that more than one person answers. Then find out what each one is: a person's mailbox, a list, or a shared mailbox. Open the Sent Items folder inside each shared mailbox. If it is empty while you know replies have gone out, the copy setting is off. Then check how full each mailbox is, so nobody finds out the hard way.
That check is the first thing we do with a business that feels like email is getting away from them. Sometimes the answer is small. Sometimes it is one checkbox.