Clear Maintenance Mode to Unlock a Site Collection in SharePoint

Problem: Another fine morning, SharePoint 2013/2016 sites started displaying a message: “We apologize for any inconvenience, but we’ve made the site read-only while we’re making some improvements.”. Same time, I noticed a backup failure E-mail from the backup software!

Root Cause:
Since the Backup failure occurred, SharePoint placed the site in read-only mode. However, all options under “Site Collection Quotas and Locks” were disabled in SharePoint 2013 Central Administration site!

Solution: Clear maintenance mode using PowerShell

This is because SharePoint site collection is set under maintenance mode. To clear maintenance mode in SharePoint, use this PowerShell script:

Add-PSSnapin Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue

#Site Collection URL
$SiteURL = "https://intranet.crescent.com/"

#Clear Maintenance mode
$Admin = new-object Microsoft.SharePoint.Administration.SPSiteAdministration($SiteURL)
$Admin.ClearMaintenanceMode()

This removes the maintenance mode in SharePoint 2013. Read more about SharePoint 2013 Maintenance Window Notifications