You cannot create or reply to a discussion item in an imported SharePoint Server 2013 community site

Symptoms

When you try to create a new discussion item or reply to a discussion item in a Microsoft SharePoint Server 2013 community site, you receive the following error message: 
Sorry, something went wrong
Cannot complete this action.
Please try again.

This issue occurs if the community site is a subsite that is imported from a top-level site.

Resolution

To resolve this issue, run the following Windows PowerShell cmdlets: 
$web2 = get-spweb  <URL of the nonworking sub site> 
$l2 = $web2.Lists.TryGetList("Discussions List")
$f2 = $l2.Fields.GetField("MemberLookup")
$f2.Sealed = $false
$f2.Update()
$f2.RelationshipDeleteBehavior = 2
$f2.Update()
Note These cmdlets set the value of the RelationshipDeleteBehavior property to 2. This resolves the issue.

More Information

You see errors that resemble the following in the SharePoint Server 2013 ULS logs: 
04/15/2015 15:25:34.91 w3wp.exe (0x09B4) 0x1580 SharePoint Foundation Lookup Relationships f8qz High LockManager: A Web Lock should have been taken here. xxx
04/15/2015 15:25:34.91 w3wp.exe (0x09B4) 0x1580 SharePoint Foundation General 8kh7 High Cannot complete this action.  Please try again. xxx
04/15/2015 15:25:34.91 w3wp.exe (0x09B4) 0x1580 SharePoint Foundation General aix9j High SPRequest.AddOrUpdateItem: UserPrincipalName=i:0).w|s-1-5-21-xxx-xxx-xxx-500, AppPrincipalName= ,bstrUrl=http://false/,bstrListName={xxx} ,bAdd=True ,bSystemUpdate=False ,bPreserveItemVersion=False ,bPreserveItemUIVersion=False ,bUpdateNoVersion=False ,pbstrNewDocId=00000000-0000-0000-0000-000000000000 ,bHasNewDocId=False ,bstrVersion=<null> ,bCheckOut=False ,bCheckin=False ,bUnRestrictedUpdateInProgress=False ,bMigration=False ,bPublish=False ,bstrFileName=<null> xxx
Proprietà

ID articolo: 3060489 - Ultima revisione: 10 mar 2016 - Revisione: 1

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