原因：IIS7服务器默认没有支持axd格式的MIME。
解决方法：通过修改Web.config来解决。
<system.webServer>
<validationvalidateIntegratedModeConfiguration="false"/>
<modules>
<removename="ScriptModule"/>
<addname="ScriptModule"preCondition="managedHandler"type="System.Web.Handlers.ScriptModule,System.Web.Extensions,Version=3.5.0.0,Culture=neutral,PublicKeyToken=31BF3856AD364E35"/>
</modules>
<handlers>
<removename="WebServiceHandlerFactory-Integrated"/>
<removename="ScriptHandlerFactory"/>
<removename="ScriptHandlerFactoryAppServices"/>
<removename="ScriptResource"/>
<addname="ScriptHandlerFactory"verb="*"path="*.asmx"preCondition="integratedMode"type="System.Web.Script.Services.ScriptHandlerFactory,System.Web.Extensions,Version=3.5.0.0,Culture=neutral,PublicKeyToken=31BF3856AD364E35"/>
<addname="ScriptHandlerFactoryAppServices"verb="*"path="*_AppService.axd"preCondition="integratedMode"type="System.Web.Script.Services.ScriptHandlerFactory,System.Web.Extensions,Version=3.5.0.0,Culture=neutral,PublicKeyToken=31BF3856AD364E35"/>
<addname="ScriptResource"preCondition="integratedMode"verb="GET,HEAD"path="ScriptResource.axd"type="System.Web.Handlers.ScriptResourceHandler,System.Web.Extensions,Version=3.5.0.0,Culture=neutral,PublicKeyToken=31BF3856AD364E35"/>
<addname="WebResource"verb="GET"path="WebResource.axd"preCondition="integratedMode"type="System.Web.Handlers.AssemblyResourceLoader"/>
<addname="cachedimageservice"verb="GET"path="cachedimageservice.axd"preCondition="integratedMode"type="MsdnMag.CachedImageService,DynamicImage"/>
<addname="Reserved.ReportViewerWebControl"verb="*"path="Reserved.ReportViewerWebControl.axd"preCondition="integratedMode"type="Microsoft.Reporting.WebForms.HttpHandler,Microsoft.ReportViewer.WebForms,Version=9.0.0.0,Culture=neutral,PublicKeyToken=b03f5f7f11d50a3a"/>
</handlers>
<staticContent>
<removefileExtension=".axd"/>
<mimeMapfileExtension=".axd"mimeType="image/bmp"/>
</staticContent>
</system.webServer>
关键是其中跟axd相关的配置。
