SSRS 2008 x64 add-in Error

Event Type: Error
Event Source: Windows SharePoint Services 3
Event Category: Runtime
Event ID: 6611
Date: 11/25/2008
Time: 1:59:18 PM
User: N/A
Computer: WebFrontEnd Server
Description:
Error: Failure in loading assembly: Microsoft.ReportingServices.SharePoint.UI.WebParts, Version=9.0.242.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91

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