Can somebody please help track down this error. All was fine until the site was upgraded:

4.9 to 4.10 to 4.11.1 to 6rc 

I can provide any files (or even remote access). Would like to get this sorted out.

Server Error in '/' Application.

Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

[No relevant source lines]

Source File: c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\bf2bc25b\558f288d\App_Web_uploadmediaimage.ascx.c3c18f9f.j3r7f2hb.0.cs Line: 0

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
   umbraco.cms.businesslogic.datatype.DataTypeDefinition.get_DataType() +149
   umbraco.cms.businesslogic.datatype.DataTypeDefinition.<GetByDataTypeId>b__0(DataTypeDefinition x) +6
   System.Linq.WhereArrayIterator`1.MoveNext() +55
   umbraco.cms.businesslogic.datatype.DataTypeDefinition.GetByDataTypeId(Guid DataTypeId) +222
   umbraco.controls.Images.UploadMediaImage..ctor() +52
   ASP.umbraco_controls_images_uploadmediaimage_ascx..ctor() in c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\bf2bc25b\558f288d\App_Web_uploadmediaimage.ascx.c3c18f9f.j3r7f2hb.0.cs:0
   ASP.umbraco_plugins_tinymce3_insertimage_aspx.__BuildControlMediaUploader() in c:\Inetpub\wwwroot\beananimal_v4\umbraco\plugins\tinymce3\insertImage.aspx:187
   ASP.umbraco_plugins_tinymce3_insertimage_aspx.__BuildControlpane_upload() in c:\Inetpub\wwwroot\beananimal_v4\umbraco\plugins\tinymce3\insertImage.aspx:186
   ASP.umbraco_plugins_tinymce3_insertimage_aspx.__BuildControlForm1() in c:\Inetpub\wwwroot\beananimal_v4\umbraco\plugins\tinymce3\insertImage.aspx:150
   ASP.umbraco_plugins_tinymce3_insertimage_aspx.__BuildControlTree(umbraco_plugins_tinymce3_insertimage_aspx __ctrl) in c:\Inetpub\wwwroot\beananimal_v4\umbraco\plugins\tinymce3\insertImage.aspx:1
   ASP.umbraco_plugins_tinymce3_insertimage_aspx.FrameworkInitialize() in c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\bf2bc25b\558f288d\App_Web_insertimage.aspx.43b758d9.hbekvrgs.0.cs:0
   System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +54
   System.Web.UI.Page.ProcessRequest() +78
   System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) +21
   System.Web.UI.Page.ProcessRequest(HttpContext context) +49
   ASP.umbraco_plugins_tinymce3_insertimage_aspx.ProcessRequest(HttpContext context) in c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\bf2bc25b\558f288d\App_Web_insertimage.aspx.43b758d9.hbekvrgs.0.cs:0
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +100
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319

For anybody having this issue in the future:

It would appear that when you click on "Insert Edit/Image" in the Rich Text Editor Control, The cmsDataType table read. In my case there was a data type referenced (Mass Mailer or something like that) that was removed as part of the upgrade...

My guess is that when I removed uninstalled a PACKAGE that the associated data type was orphaned and broke umbraco because "Insert/Edit image button must itterate through all of the data types when it is clicked...

Packages are essential, but there has to be a better way to ensure that they don't break functionality when they are uninstalled, or at least package authors should be required to provide a fully functional uninstall script before a package is listed in the repository. I am finding trash all over my installation from several years worth of package installs/upgrades/uninstalls.

Anybody have any thoughts on how to improve the functionality?

I'm having the same issue after upgrade on the default media picker with the Advanced Dialog option set.  It works fine with the basic picker, but the advanced version throws the exception.

Hi William

How did you trace which cotrol was causing the problem?

Thanks

To answer my own question click through all the datatypes till you find the DataType that causes the issue

William, 

your post was exactly what i needed thank you very much.

It was Data Type. Thank you.

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