Forum Discussion
Extend M365 Archive Quota capacity
In my organization, we are currently on the O365 E5 License with default 100GB mailbox size per user and 1.5TB archive quota.
However, due to organizational policy and regulatory requirements, we are expected to keep all the data from inception. Hence, the requirement for a solution to extend our archive size from 1.5TB.
From the official Microsoft documentation, https://learn.microsoft.com/en-us/office365/servicedescriptions/exchange-online-archiving-service-description/exchange-online-archiving-service-description#archive-storage-quota the maximum expansion of the archive mailbox is 1.5TB.
Is it possible to extend the archive storage to an Azure blob? Like an automated script that moves the data from the Archive mailbox for each user to the Azure blob or any other storage service that does not have storage size limitation. I am open to suggestions. Thanks
2 Replies
Yes, since you are on the Office 365 E5 license, your users are eligible for auto-expanding archive mailboxes. By default, archive storage starts at 100GB, but Microsoft automatically increases it in 100GB increments up to 1.5TB and beyond as needed, based on usage.
Once a user's archive mailbox reaches 90% of its capacity, Exchange Online starts expanding it in the background. There's no need for manual intervention, but it can take some time depending on the load.
You can check if auto-expanding archive is enabled using PowerShell:
Get-Mailbox "User Name" | FL ArchiveStatus,AutoExpandingArchiveEnabled
And to enable it (if needed):
Enable-Mailbox "User Name" -AutoExpandingArchive
If you hae reached the upper limits and it's not expanding, I’d recommend raising a support ticket with Microsoft for further review.
Yes, below are the steps and considerations:
- Use PowerShell + Microsoft Graph API or EWS Managed API to extract mailbox content.
- Store extracted data in Azure Blob Storage, which offers virtually unlimited capacity.
- Automate the process with Azure Functions or Logic Apps to run scheduled exports.
- Considerations:
- You’ll lose native search and compliance features unless you re-index the data.
- You’ll need to manage encryption, retention, and access controls manually.
- This approach is best for cold data that’s rarely accessed but must be retained.
- Use PowerShell + Microsoft Graph API or EWS Managed API to extract mailbox content.
