UPDATE: this problem isn't isolated to Courier, I just tried installing another package (CMS Import) and I'm receiving the exact same exception happening at the same point in the install process (when the back office attempts to re-load).

2015-07-15 16:25:58,409 [6] INFO  Umbraco.Core.UmbracoApplicationBase - [P7364/T1/D2] Application shutdown. Reason: BinDirChangeOrDirectoryRename
2015-07-15 16:26:06,946 [16] ERROR Umbraco.Core.UmbracoApplicationBase - [P7364/T1/D8] An unhandled exception occurred
System.ArgumentException: The relative virtual path 'function ExecuteTask(){ UmbClientMgr.contentFrame('/umbraco/plugins/CMSImport/Pages/wizard.aspx?executetask=true&importid=' + UmbClientMgr.mainTree().getActionNode().nodeId);UmbClientMgr.closeModalWindow(); }' is not allowed here.

UPDATE2: when I point the Umbraco install at a SQL ce database, I don't get the error, however this isn't an acceptable solution since I need to duplicate our server environment as much as possible and certain packages aren't compatible with SQL ce.

I've encounter the same issue while upgrading Umbraco from v7.1.2 to v7.2.7. I've followed the steps described in the documentation, copy /bin; /Umbraco; /Umbraco_Client folders.

Error is received when Umbraco finishes installing and when reloading the white screen is displayed. I've checked the requests and saw that the following are failing with error 500:

http://test.xxx.com/umbraco/Application?umb__rnd=ffffffffd45178f3

[ArgumentException: The relative virtual path 'function ShowTransferItemModal(){ 


                      var nodeId = UmbClientMgr.mainTree().getActionNode().nodeId;
                      var nodeType = UmbClientMgr.mainTree().getActionNode().nodeType;
                      var nodeName = UmbClientMgr.mainTree().getActionNode().nodeName;

                      /could also use some failure alerts, just in case

                      var providerguid = 'temp';
                      var itemid = 'temp';

                        jQuery.ajax({
                          type: "POST",
                          url: "/umbraco/plugins/courier/webservices/Courier.asmx/GetProviderId",
                          data: "{treeType: '" + nodeType + "'}",
                          contentType: "application/json; charset=utf-8",
                          dataType: "json",
                          success: function(msg) {

                            providerguid = ...' is not allowed here.]


System.Web.VirtualPath.Create(String virtualPath, VirtualPathOptions options) +12538529
   System.Web.VirtualPathUtility.ToAbsolute(String virtualPath, String applicationPath) +20
   Umbraco.Core.IO.IOHelper.ResolveUrl(String virtualPath) +372
   System.Linq.WhereSelectArrayIterator2.MoveNext() +82
   System.Collections.Generic.List1..ctor(IEnumerable1 collection) +536
   System.Linq.Enumerable.ToList(IEnumerable1 source) +80
   Umbraco.Web.Editors.BackOfficeController.GetLegacyActionJs(LegacyJsActionType type) +159
   Umbraco.Web.Editors.BackOfficeController.Application() +203
   lambda_method(Closure , ControllerBase , Object[] ) +43
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary2 parameters) +258
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary2 parameters) +39
   System.Web.Mvc.Async.<>cDisplayClass42.<BeginInvokeSynchronousActionMethod>b41() +34
   System.Web.Mvc.Async.<>cDisplayClass39.<BeginInvokeActionMethodWithFilters>b33() +124
   System.Web.Mvc.Async.<>cDisplayClass4f.<InvokeActionMethodFilterAsynchronously>b49() +787435
   System.Web.Mvc.Async.<>cDisplayClass4f.<InvokeActionMethodFilterAsynchronously>b49() +787435
   System.Web.Mvc.Async.<>cDisplayClass4f.<InvokeActionMethodFilterAsynchronously>b49() +787435
   System.Web.Mvc.Async.<>cDisplayClass4f.<InvokeActionMethodFilterAsynchronously>b49() +787435
   System.Web.Mvc.Async.<>cDisplayClass37.<BeginInvokeActionMethodWithFilters>b36(IAsyncResult asyncResult) +15
   System.Web.Mvc.Async.<>cDisplayClass2a.<BeginInvokeAction>b20() +33
   System.Web.Mvc.Async.<>cDisplayClass25.<BeginInvokeAction>b22(IAsyncResult asyncResult) +787916
   System.Web.Mvc.<>cDisplayClass1d.<BeginExecuteCore>b18(IAsyncResult asyncResult) +28
   System.Web.Mvc.Async.<>cDisplayClass4.<MakeVoidDelegate>b3(IAsyncResult ar) +15
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +65
   System.Web.Mvc.Async.<>cDisplayClass4.<MakeVoidDelegate>b3(IAsyncResult ar) +15
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +51
   System.Web.Mvc.<>cDisplayClass8.<BeginProcessRequest>b3(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>cDisplayClass4.<MakeVoidDelegate>b3(IAsyncResult ar) +15
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +51
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +606
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +288

Thanks, Stanislav! I finally resolved this. I think the database I was using was corrupted (even though I was deleting it and re-creating it every time). When I created a new database with a different name, uoolah! It worked!

Hi, today I saw that there is a new version from umbraco 7.2.8. With this version the upgrade process completed without error. I guess that there was some bug in v7.2.7.

Hmmmm... that's the version I installed when this mysteriously fixed itself... I wonder.

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