To check on the status of your mailboxes and adjust their quota follow these steps:

  1. Log in to Plesk
  2. Choose the Mail tab on the left. Here you will see all email addresses along with their capacity and current size.
  3. Click on the email account if you wish to adjust the quota
  4. Under “Mailbox” you may specify a size. You cannot increase it beyond the maximum hard limit for your hosting plan (shown below).

If you spot any mail accounts you are not currently using at Step 2 above, it’s best to remove them now. This will help free up space and prevent potential abuse of stale email accounts in the future.

See the bottom of this page for a video walk-through.

Mail Hard Limits

Please note that the maximum possible quota / storage limit per mail account is as follows as of Jan 2019:

  • Helium Hosting: 1 Mailbox @ 100MB
  • Carbon Hosting: 25 Mailboxes @ 2GB each
  • Titanium Hosting: Unlimited Mailboxes @ 5GB each
  • Premium Mail: The storage limit you ordered.
  • Exchange Mail: Either 50GB (most common) or 300GB per account, if you ordered the larger capacity option.

These are hard limits per account in order to ensure our hosting plans are able to function on high-performance solid state drives (SSDs). Using SSDs means excellent website speed, but it also means we have to take our storage limitations very seriously, as SSDs are more limited in capacity than traditional hard drives.

The Fix: Reduce Storage or Upgrade

Here’s a few options to help resolve a full mailbox:

  1. Delete messages using your mail app or webmail. Specifically finding and removing messages with large attachments, like videos, photos, and other attachments like PDFs will help the most. When logged in to webmail, click on any given mail folder where you store lots of messages, then in the search box at the top of the message listing, enter size:5M to see all message in the mail folder that are 5MB and larger. Delete all that you can. You may also wish to save the attachments in the messages to your computer (just click on the message, then click on any attachments you wish to save) prior to removing them. Once you’re done removing, you must click on the Trash folder, then the “Clear Folder” option at the top of the Trash messages list to empty the trash, removing them permanently.
  2. Archive older messages to your computer, then remove them from the server. This guide will help you learn how.
  3. Aggressive Spam Filtering: if this is a mailbox that you rarely use, and is filling up with spam, set the spam filter to delete spam, with the score threshold set to 1. This way it minimizes the amount of illegitimate email being stored in the mailbox.
  4. Upgrade your hosting plan: if you’re currently on our Helium or Carbon hosting plans, upgrading to the next plan up will allow you a larger maximum per-mailbox limit as listed above. Note: Titanium mailboxes at 5GB max each are the upper limit for hosting your mail on our shared hosting plans. If you cannot reduce your mail storage lower than 5GB, moving to Exchange hosting is your best bet:
  5. Move mail to Microsoft Exchange Hosting to get 50GB per mailbox for $9.99 per mailbox monthly or $99.99 / year.
  6. You may review all mail hosting options for comparison here.

If you opted for options 1 or 2 or both, you must wait for the mail app (or webmail) to update the server after emptying the trash or moving the messages. With larger numbers of messages, this can take an hour or two!

How to refresh mailbox storage usage in Plesk

To see the updated mailbox usage in Plesk, follow steps 1 and 2 at the top of this post so you are looking at the list of mail accounts. Check the box to the left of the account where you believe you have reduced its server storage, then click the box called “Refresh Usage Stats” at the top of the page. The new storage usage will now be showing.

If you do not see a reduction in server storage for the mail account, it is because either you haven’t cleared up enough emails with larger attachments OR you haven’t waited long enough for the mail app to sync with the server. Check back 24 hours later to ensure sufficient time to sync.

Plesk Quota Settings Video Walkthrough

If you prefer to watch, the video below will walks you through managing the mailbox quota in Plesk 10+ (this may differ from your version of Plesk). Whether you need to increase or decrease your quota, this video will show you how.

The following video will walk you through changing your mailbox quota in Plesk 9. If you’re running into mailbox limits or would like to keep your mailboxes limited lower than the default, check out the video below.

If you have any questions about the above video, or anything dealing with mailbox quotas with Plesk, open a support ticket or feel free to connect with us on Twitter.

About Jordan Schelew

Jordan has been working with computers, security, and network systems since the 90s and is a managing partner at Websavers Inc. As a founder of the company, he's been in the web tech space for over 15 years.

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