Problem occurring in each LS Venture

Hello,

I'm having this problem while attempting to turn the application on. It’s occurring in each LS venture. Is anybody familiar with the problem or how to repair it? I previously attempted to re-set LS, but nothing's change. Please can anyone provide me a suggestion about it specially, if you have faced this situation before.

Error:

An unhandled exception (Error no controlado en una aplicacion de silverlight

code 4004

Category:ManagedRuntimeError

Message:System.BadImageFormatException:No se puede carger el archivo o ensamblado'System.Core,Version=5.0.5.0,Culture=netural,PublicKeyToken=7cec85d7bea7798e'ni una de sus dependencis.Formato de archivo de ensamblado no valido.(eXCEPCION DE  HRESULT:0x8013141d)

File name: System.Core.Version = 5.0.5.0, Culture= neutral,

PublicKeyToken = 7cec85d7bea7798e’

at

MicrosoftLightSwitch.Performance.Framework.lnternal.CodeMarkerPlatfo…

enableCodeMarkers, Boolean& remoteBlockingMode. IList’1& enableList)

at

Microsoft.LightSwitch.Performance.Framework.lnternal.CodeMarkerPlatfo…

at

Microsoft.LightSwitch.Performance.Framework.Internal.CodeMarkerPlatform id)

at

Microsoft.LightSwitch.Performance.InternaLCodeMarker.Ensu relnitialized()

at

Microsoft.LightSwitch.PerformanceJnternal.CodeMa rker.Mark(CodeMarke… id)

at

Microsoft.LightSwitch.Runtime.Shelilmplementation.App..ctorO ) occurred in iexplore.exe [3740].