Last updated on June 9th, 2022 at 05:03 am
Office 365 accounts have many advantages. All account data and details are completely secure and available worldwide. You can instantly update any document or spreadsheet with versioning. Also, previous versions of the file are also available. The Office 365 account has limitations, just like other services. You can only use the features that are available to you as part of your Microsoft 365 subscription. It is important to remember these limitations and not exceed them. You can find the current mailbox size and usage by visiting the mailbox usage section of the Office 365 Admin Center, or the Exchange Online Admin Center.
You get different types of notifications and messages depending on the mailbox size.
- Warning: A warning email is sent to users when their mailbox exceeds the limit. Once the warning email arrives, the user must delete all non-critical messages.
- Prohibit Send: A user will receive the prohibit-send email notification if their mailbox exceeds the maximum size. You will be prohibited from sending any further messages to other users in such a situation.
- Block send/receive: Office 365 won’t allow new incoming email if the mailbox size limit has been exceeded. It will send a Non-delivery Report (NDR), to the sender. You must delete all non-critical emails in your inbox to stop receiving new emails.
This table shows the mailbox size limit for each Office 365 plan.
| Office365 Plan | User Mailboxes | Archive Emailboxes | Shared mailboxes | Resource Mailboxes | Site Mailboxes | Public Folder Emailboxes | Group Mailboxes |
| Business Essentials | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB |
| Business Premium | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB |
| Enterprise E1 | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB | 50 GB |
| Enterprise E3 | 100 GB | Unlimitable | 50 GB | 50 GB | 50 GB | 100 GB | 50 GB |
| Enterprise E5 | 100 GB | Unlimitable | 50 GB | 50 GB | 50 GB | 100 GB | 50 GB |
| Enterprise F3 | 2 GB | Not available | 50 GB | 50 GB | Not available | Not available | 50 GB |
Important facts about Office 365 Mailbox Storage
- Office 365 users get 100 GB storage space in their archive mailbox. When the archive mailbox reaches 100 GB, the auto-expanding option is activated.
- Exchange Online subscriptions are required to access the shared mailbox. The shared mailbox can only hold 50GB without a license. You can increase the limit by purchasing the Exchange Online subscription. The shared mailbox size will then be 100 GB.
- To access the resource mailbox, you don’t need a license. Its default size is 50GB. The user can increase its size by purchasing an Office 365 E3 subscription or E5.
PowerShell – Increase Office 365 Mailbox Size by 100 GB
We all use at least one of these Office 365 plans, and we all take advantage of all the mailboxes. To make room for new email, you’ll need to delete any emails that exceed this limit. You can also choose to save your email from Office 365 mailbox storage, or to store it locally on your system drive. The Exchange Shell commands allow you to increase the mailbox size. Here’s the complete procedure.
- Start Windows PowerShell as administrator by selecting the Windows PowerShell icon, right-clicking and selecting Run as administrator option. $UserCredential = Get-Credential This command will open the Credential Request Dialog Box where you can enter the credentials for your Office 365 account.
- To create a new Exchange Online session, you will need to run the following command. $Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri https://outlook.office365.com/powershell-liveid/ -Credential $UserCredential -Authentication Basic -AllowRedirection
- Use the following command to import the Exchange Online cmdlets into your local session. Import-PSSession $Session -DisableNameChecking
- This command will give you the mailbox size limit. Select *quota
- To increase your mailbox size limit to 100 GB, run this command Set-Mailbox < UserID > -ProhibitSendQuota < Value > -ProhibitSendReceiveQuota < Value > -IssueWarningQuota Here’s an example of a command-line. Set-Mailbox charlie@yourmail.com -ProhibitSendQuota 99GB -ProhibitSendReceiveQuota 98GB -IssueWarningQuota 98GB This will allow you to fix the increased storage warning quota of 98 GB, and the send quota of 99 GB, so you can have 100 GB storage in you mailbox.
You can use a different command to apply the changes to multiple users if you have a criterion. Get-User | where $_.Team -eq “Developer” | Get-Mailbox | Set-Mailbox -ProhibitSendQuota 99GB -ProhibitSendReceiveQuota 98GB -IssueWarningQuota 98 GB You have now increased the mailbox size for the entire team of developers to 100 GB.
NOTE: To make any changes to multiple accounts, you will need Administrator privileges. - This command can be used to limit mailbox size for all users in an organization. Get-Mailbox | Set-Mailbox -ProhibitSendQuota < Value > -ProhibitSendReceiveQuota < Value > -IssueWarningQuota < Value >
- You can end the session after making all necessary changes. Remove-PSSession $Session
Conclusion
If you are familiar with Windows PowerShell commands, the above procedure is easy to follow. You can increase the mailbox size limit for a single or multiple Office 365 account. However, you must remember that it will not affect other limitations such as mailbox folder limits, retention limits and moderation limits. First, take Microsoft 365 Backup before you increase your mailbox size. Next, you will need to check what other restrictions you have to raise to maximize the use of the increased mailbox storage.