How to delete broken EventReceiverDefinitions

When you use SharePoint 2010 event receivers for sites, webs or list you may get a broken event receiver definitions. It could be due to incorrect event receivers managment, you used packages that left broken event receiver definitions or something like that.

It is too hard to manually remove all broken definitions from whole site collection. I do not know useful tool for this purpose.

The following script do it for you. It is iterates through all webs and lists into site collection and remove all event receiver definitions that point to not exist assemblies.

open Microsoft.SharePoint

module EventReceiversCleaner =
    let private isAssemblyExist (assemblyName:string) =
        try
            match System.Reflection.Assembly.Load(assemblyName) with
             | null -> false
             | assembly -> assemblyName = assembly.FullName
        with
         | e -> false

    let private removeCandidates = ref List.Empty

    let CollectBroken (collection:SPEventReceiverDefinitionCollection) =
        for er in collection do
            if not (isAssemblyExist er.Assembly) then
                removeCandidates := er :: !removeCandidates

    let RemoveAll() =
        !removeCandidates |> List.iter
            (fun (er:SPEventReceiverDefinition) ->
                let name = sprintf "Assembly:'%s'" er.Assembly
                try
                    er.Delete()
                    printfn "Deleted : %s" name
                with
                 | e -> printf "Failed to delete: %s" e.Message)

try
    let url = "http://localhost/"
    printfn "Connecting to '%s'..."  url
    use site = new SPSite(url)
    site.EventReceivers |> EventReceiversCleaner.CollectBroken

    let rec collectFromLists (web:SPWeb) =
        printfn "Processing web '%s'..." web.ServerRelativeUrl
        web.EventReceivers |> EventReceiversCleaner.CollectBroken
        web.Webs |> Seq.iter collectFromLists

        for list in web.Lists do
            printfn "Processing list '%s'..." list.Title
            list.EventReceivers |> EventReceiversCleaner.CollectBroken

    use web = site.OpenWeb()
    collectFromLists web

    EventReceiversCleaner.RemoveAll()
    printfn "Finished."
with
    | e -> printfn "Exception : %s" e.Message

System.Console.ReadLine() |> ignore

P.S. You should compile it using .NET 3.5 and 64 bit project.