What happens to email when the mailbox or hosting is full

When the mailbox or the hosting reaches its space limit, the server may not have room to store new messages. Freeing up space allows new deliveries, but it does not automatically recover every email sent while the problem lasted.

Check which limit has been reached

Check the address's quota in cPanel > Email Accounts > Manage and the total usage of the hosting. A mailbox can have room within its quota and still fail because the whole hosting is full. Raising only the mailbox quota does not upgrade the plan.

In the client area, go to Hosting > your service > Space to check how much room the service has. The What you can free up tab lists clean-up options you should weigh up before acting.

Keep what you need and free up space selectively, or adjust the capacity where appropriate. The indicators can take a while to update.

If the lack of space even stops webmail from opening, check whether your service offers the temporary space increase. It can give you room to clean up or upgrade the plan; check its conditions and sort out the usage before it ends.

Find out what happened to each message

Check Track Delivery and, if there is one, the notice the sender received:

• A temporary (4xx) response asks the sending server to try again. That server decides the intervals and how long it keeps the message; its queue may eventually expire.
• A permanent (5xx) response causes a rejection. Once the quota is sorted out, the sender has to send it again.

The configuration and the limit reached determine the response. Do not assume that every message was left waiting or that every one was permanently rejected.

Check that it has recovered

Test receiving from another account of your own and check the message in webmail. For an important email that is still missing, ask the sender for the delivery notice or to send it again once the space is recovered. If you need support, give the address, the approximate time and the error; there is no need to share the password.