Below Power Shell Script will Unlock a SharePoint site if it is in locked/read-only.
#Region variable declaration
Write-Host “UnLock status started…..”
Add-PSSnapin Microsoft.Sharepoint.Powershell
Set-SPSite -Identity “<site-url>” -LockState “Unlock”
Write-Host “Task completed…..”
Read-Host -Prompt “The above error occurred. Press Enter to exit.”
For -LockState attribute there are mainly 4 parameters that can be used:
Unlock – To unlock site collection and make it available to users.
NoAdditions – Prevent users from adding new content to the site collection. Updates and deletions are still allowed.
ReadOnly – Prevent users from adding, updating, or deleting content.
NoAccess – Prevent users from accessing the site collection and its content.