无法加载文件或程序集'System.Core，Version = 2.0.5.0，Culture = neutral，PublicKeyToken = 7cec85d7bea7798e，Retargetable = Yes'

Question

我有一个vimeo API dll用于将视频上传到Vimeo服务器，它在开发服务器上运行良好，但在移动到Live服务器后它无效。它会抛出此错误

{"Message":"An error has occurred.","ExceptionMessage":"Could not load file or assembly 'System.Core
, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e, Retargetable=Yes' or one of its
 dependencies. The given assembly name or codebase was invalid. (Exception from HRESULT: 0x80131047)"
,"ExceptionType":"System.IO.FileLoadException","StackTrace":"   at System.Reflection.CustomAttribute
._CreateCaObject(RuntimeModule pModule, IRuntimeMethodInfo pCtor, Byte** ppBlob, Byte* pEndBlob, Int32
* pcNamedArgs)\r\n   at System.Reflection.CustomAttribute.CreateCaObject(RuntimeModule module, IRuntimeMethodInfo
 ctor, IntPtr& blob, IntPtr blobEnd, Int32& namedArgs)\r\n   at System.Reflection.CustomAttribute.GetCustomAttributes
(RuntimeModule decoratedModule, Int32 decoratedMetadataToken, Int32 pcaCount, RuntimeType attributeFilterType
, Boolean mustBeInheritable, IList derivedAttributes, Boolean isDecoratedTargetSecurityTransparent)\r
\n   at System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeMethodInfo method, RuntimeType caType
, Boolean inherit)\r\n   at System.Reflection.RuntimeMethodInfo.GetCustomAttributes(Boolean inherit)
\r\n   at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.InitializeProperties(MethodInfo methodInfo
)\r\n   at System.Web.Http.Controllers.ReflectedHttpActionDescriptor..ctor(HttpControllerDescriptor controllerDescriptor
, MethodInfo methodInfo)\r\n   at System.Web.Http.Controllers.ApiControllerActionSelector.ActionSelectorCacheItem
..ctor(HttpControllerDescriptor controllerDescriptor)\r\n   at System.Web.Http.Controllers.ApiControllerActionSelector
.<>c__DisplayClass2.<GetInternalSelector>b__0(Object _)\r\n   at System.Collections.Concurrent.ConcurrentDictionary
`2.GetOrAdd(TKey key, Func`2 valueFactory)\r\n   at System.Web.Http.Controllers.ApiControllerActionSelector
.GetInternalSelector(HttpControllerDescriptor controllerDescriptor)\r\n   at System.Web.Http.Controllers
.ApiControllerActionSelector.SelectAction(HttpControllerContext controllerContext)\r\n   at System.Web
.Http.ApiController.ExecuteAsync(HttpControllerContext controllerContext, CancellationToken cancellationToken
)\r\n   at System.Web.Http.Dispatcher.HttpControllerDispatcher.SendAsyncInternal(HttpRequestMessage request
, CancellationToken cancellationToken)\r\n   at System.Web.Http.Dispatcher.HttpControllerDispatcher.SendAsync
(HttpRequestMessage request, CancellationToken cancellationToken)"}

这有什么理由吗？指导我解决这个问题。