I've got Events installed against DNN v4.9.4, yet the module throws errors. To add to my confusion, asp.net 3.5 is installed, and not sure what the AJAX needs are because of that fact.
The error is such that
DotNetNuke.Services.Exceptions.ModuleLoadException: c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\root\5e1e42ff\98f03ce9\App_Web_recurrenceeditor.ascx.8bd47417.exlckntp.0.cs(2399): error CS0433: The type 'System.Web.UI.AsyncPostBackTrigger' exists in both 'c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\root\5e1e42ff\98f03ce9\assembly\dl3\94052a48\00f8aa38_cd69c801\System.Web.Extensions.DLL' and 'c:\Windows\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll' ---> System.Web.HttpParseException: c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\root\5e1e42ff\98f03ce9\App_Web_recurrenceeditor.ascx.8bd47417.exlckntp.0.cs(2399): error CS0433: The type 'System.Web.UI.AsyncPostBackTrigger' exists in both 'c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\root\5e1e42ff\98f03ce9\assembly\dl3\94052a48\00f8aa38_cd69c801\System.Web.Extensions.DLL' and 'c:\Windows\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll' ---> System.Web.HttpCompileException: c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\root\5e1e42ff\98f03ce9\App_Web_recurrenceeditor.ascx.8bd47417.exlckntp.0.cs(2399): error CS0433: The type 'System.Web.UI.AsyncPostBackTrigger' exists in both 'c:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files\root\5e1e42ff\98f03ce9\assembly\dl3\94052a48\00f8aa38_cd69c801\System.Web.Extensions.DLL' and 'c:\Windows\assembly\GAC_MSIL\System.Web.Extensions\3.5.0.0__31bf3856ad364e35\System.Web.Extensions.dll' at System.Web.Compilation.BuildManager.PostProcessFoundBuildResult(BuildResult result, Boolean keyFromVPP, VirtualPath virtualPath) at System.Web.Compilation.BuildManager.GetBuildResultFromCacheInternal(String cacheKey, Boolean keyFromVPP, VirtualPath virtualPath, Int64 hashCode) at System.Web.Compilation.BuildManager.GetVPathBuildResultInternal(VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.Compilation.BuildManager.GetVPathBuildResultWithNoAssert(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.UI.BaseTemplateParser.GetReferencedType(VirtualPath virtualPath, Boolean allowNoCompile) at System.Web.UI...
You get the idea.
Any advice appreciated.