Any OneDrive for Business user whose storage allocation has been manually set above their Microsoft 365 licence entitlement will enter a read-only state once the rollout completes in June 2026. Microsoft began deploying this enforcement change in late May 2026, and it applies to all commercial, GCC, GCC High, and DoD environments.
What Is Changing: MC1310684 Explained
SharePoint Online has long allowed administrators to manually adjust the storage quota for an individual user's OneDrive for Business account, sometimes setting it higher than what the user's licence actually entitles them to. A user holding a Microsoft 365 E3 licence is entitled to 5 TB of OneDrive storage, but an admin could override that to 10 TB or more without SharePoint preventing it. Similarly, Office 365 A1 licences entitle users to 100 GB, but many A1 accounts created before Microsoft introduced consistent A1 storage enforcement were provisioned with 1 TB or 5 TB and have never been corrected.
MC1310684 closes that gap. Going forward, SharePoint will enforce OneDrive storage quotas strictly against each user's licence entitlement. If a user's current allocation exceeds what their licence allows, SharePoint will reduce the quota to match. Users already exceeding their licensed storage limit go into a read-only state: they can view and download their files, but cannot upload, edit, or sync new content until their storage usage drops below the licensed limit.
Which Users Are at Risk
Not every tenant will be affected. Organisations that have never manually elevated individual OneDrive quotas above licence defaults and have no legacy A1 allocations from before the A1 storage policy was formalised may see no change at all. The scenarios most likely to produce affected users are:
- Office 365 A1 accounts with legacy over-allocation: users on A1 licences who were provisioned with 1 TB or 5 TB of OneDrive storage before the 100 GB A1 limit was enforced. Any A1 user currently storing more than 100 GB will be placed in read-only mode.
- E3 or E1 users given temporary quota increases: organisations that elevated individual quotas for a short-term project or migration and never reduced them. E3 entitles users to 5 TB; any E3 account set above 5 TB is now out of licence.
- Users with custom-elevated quotas set by a previous admin: historical quota changes are not always documented. Tenants should generate a full list of current OneDrive quotas and compare them against licence entitlements before the rollout completes.
- Users near or over their licence limit: even users whose quota was set correctly may have accumulated enough content to exceed the limit over time. A user with a 1 TB E1 entitlement who has accumulated 950 GB of OneDrive content is not immediately at risk from this change but has only 50 GB of headroom.
What Admins Should Do Before the Rollout Completes
The window to act is narrow. The rollout began in late May 2026 and is expected to complete across all tenants in June 2026. The recommended sequence is:
- Generate a quota vs. usage report for all OneDrive accounts. In the Microsoft 365 admin centre, navigate to Reports > Usage > OneDrive for Business to see per-user storage data. For a tenant with many users, exporting this via PowerShell using
Get-SPOSite -IncludePersonalSite $truegives a full list of current quotas and usage. - Cross-reference quotas against licence entitlements. Flag any user whose quota setting exceeds what their assigned licence allows. A1 users over 100 GB of actual usage are the most urgent group; they face lockout as soon as the rollout reaches them.
- Contact affected users before the cutover. Give users with over-quota accounts advance notice and a clear list of what they can delete or move to reduce their usage. Proactive communication prevents unexpected sync failures that arrive as helpdesk tickets with no context.
- Identify content that can be removed or archived. Large files, old video recordings, duplicate document sets, and content from completed projects are common sources of bloat. Users who need to reduce usage quickly benefit from a clear picture of what is consuming the most space.
- Evaluate whether a licence upgrade resolves the gap. For a small number of users who genuinely need more than their current licence provides, upgrading to a higher-tier licence (such as from E1 to E3, or from A1 to A3) is a cleaner long-term resolution than asking them to continuously trim their OneDrive.
ShareMaster's Report Master can export storage utilisation data across sites and libraries to Excel, giving administrators and compliance teams a structured view of where storage is consumed. For SharePoint site storage rather than personal OneDrive quota, see the SharePoint Online limits and quotas reference for the full tenant storage model.
Frequently Asked Questions
What is MC1310684 about?
MC1310684 is the Microsoft 365 Message Centre notification announcing that SharePoint Online will begin enforcing OneDrive for Business personal storage quotas strictly in line with each user's licence entitlement. Users whose allocated quota exceeds their licence limit will have the quota corrected, and users currently storing more than their licence allows will be placed in a read-only state until usage is reduced.
Which licences are most affected?
Office 365 A1 accounts that were provisioned with 1 TB or 5 TB before the 100 GB A1 limit was formalised are the highest-risk group. Microsoft 365 E3 or E1 users who received manual quota increases above their standard entitlement are also affected. Any user whose current quota setting is higher than what their assigned licence allows is at risk once the rollout reaches their tenant.
Does this change affect SharePoint site storage?
No. MC1310684 affects OneDrive for Business personal storage quotas only. SharePoint site collection storage is governed by the tenant's pooled storage allocation, which is not changed by this rollout. If a SharePoint site is approaching its storage limit, that is a separate issue unrelated to the licence-quota enforcement update.