Cannot create an object of type 'System.Collections.Generic.List`1

[Paul]

I'm getting the following error when I try to attach the grid to a datasource (I've tried both an ObjectDataSource and an EntityDataSource and I get the same message:

  RadGrid - RadGrid1System.Web.HttpParseException (0x80004005): Cannot create an object of type 'System.Collections.Generic.List`1[[Telerik.Web.UI.GridTableView+PersistableColumnSetting, Telerik.Web.UI, Version=2013.1.403.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4]]' from its string representation '(Collection)' for the 'ColumnSettings' property. ---> System.Web.HttpParseException (0x80004005): Cannot create an object of type 'System.Collections.Generic.List`1[[Telerik.Web.UI.GridTableView+PersistableColumnSetting, Telerik.Web.UI, Version=2013.1.403.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4]]' from its string representation '(Collection)' for the 'ColumnSettings' property. ---> System.Web.HttpException (0x80004005): Cannot create an object of type 'System.Collections.Generic.List`1[[Telerik.Web.UI.GridTableView+PersistableColumnSetting, Telerik.Web.UI, Version=2013.1.403.40, Culture=neutral, PublicKeyToken=121fae78165ba3d4]]' from its string representation '(Collection)' for the 'ColumnSettings' property. at System.Web.UI.PropertyConverter.ObjectFromString(Type objType, MemberInfo propertyInfo, String value) at System.Web.UI.ControlBuilder.AddProperty(String filter, String name, String value, Boolean mainDirectiveMode) at System.Web.UI.ControlBuilder.PreprocessAttribute(String filter, String attribname, String attribvalue, Boolean mainDirectiveMode, Int32 line, Int32 column) at System.Web.UI.ControlBuilder.PreprocessAttributes(ParsedAttributeCollection attribs) at System.Web.UI.ControlBuilder.Init(TemplateParser parser, ControlBuilder parentBuilder, Type type, String tagName, String id, IDictionary attribs) at System.Web.UI.ControlBuilder.CreateBuilderFromType(TemplateParser parser, ControlBuilder parentBuilder, Type type, String tagName, String id, IDictionary attribs, Int32 line, String sourceFileName) at System.Web.UI.ControlBuilder.GetChildPropertyBuilder(String tagName, IDictionary attribs, Type& childType, TemplateParser templateParser, Boolean defaultProperty) at System.Web.UI.ControlBuilder.CreateChildBuilder(String filter, String tagName, IDictionary attribs, TemplateParser parser, ControlBuilder parentBuilder, String id, Int32 line, VirtualPath virtualPath, Type& childType, Boolean defaultProperty) at System.Web.UI.TemplateParser.ProcessBeginTag(Match match, String inputText) at System.Web.UI.TemplateParser.ParseStringInternal(String text, Encoding fileEncoding) at System.Web.UI.TemplateParser.ProcessException(Exception ex) at System.Web.UI.TemplateParser.ParseStringInternal(String text, Encoding fileEncoding) at System.Web.UI.TemplateParser.ParseString(String text, VirtualPath virtualPath, Encoding fileEncoding) at System.Web.UI.TemplateParser.ParseString(String text, VirtualPath virtualPath, Encoding fileEncoding) at System.Web.UI.TemplateParser.ParseInternal() at System.Web.UI.TemplateParser.Parse() at System.Web.UI.DesignTimeTemplateParser.ParseControlsInternalHelper(DesignTimeParseData data, Boolean returnFirst) at System.Web.UI.DesignTimeTemplateParser.ParseControlsInternal(DesignTimeParseData data, Boolean returnFirst) at System.Web.UI.DesignTimeTemplateParser.ParseControl(DesignTimeParseData data) at System.Web.UI.Design.ControlSerializer.DeserializeControlInternal(String text, IDesignerHost host, Boolean applyTheme) at System.Web.UI.Design.ControlParser.ParseControl(IDesignerHost designerHost, String controlText, Boolean applyTheme) at System.Web.UI.Design.ControlDesigner.CreateClonedControl(IDesignerHost parseTimeDesignerHost, Boolean applyTheme) at System.Web.UI.Design.ControlDesigner.CreateViewControl() at System.Web.UI.Design.ControlDesigner.CreateViewControlInternal() at System.Web.UI.Design.ControlDesigner.get_ViewControl() at Telerik.Web.Design.RadGridDesigner.GetDesignTimeHtml(DesignerRegionCollection regions) at System.Web.UI.Design.ControlDesigner.GetViewRendering(ControlDesigner designer) 

[Keith]

Getting the same issue when applying a data source.  Seem to happen after upgrading to upgrading to 2013.1.403.40. 

[Garry Goon]

Same issue here after upgrading to 2013.1.403.40

[Michael]

same issue here

[Les]

I have the same problem.

[Dan]

I also have this issue after upgrading to 2013.1.403.40.  Deleting MasterTableView attribute ColumnSettings="(Collection)" fixed the error for me.

Honestly, does Telerik still test their controls before they release them?  I am not impressed with the number of bugs in the Q1 2013 release.

[Christophe]

We are evaluating Telerik Same issue with my very first simple DataGrid!!!!!
Not impressed so far neither.
Any fix???

[Donovan]

I also have exactly the same error after doing a clean install for evaluation purposes of 2013.1.403.45 when using the grid control. Hooking up my data access layer (which contains a single method returning a dataset) to a plain old grid view works without a hitch.

Anybody got any feedback as of yet?

[Dan]

I have not seen any feedback from Telerik, but if you see my earlier post and delete the Master Table View attribute that I'm talking about (ColumnSettings="(Collection)") in your source view the grid will work for you.

[John]

I'm evaluating the Telerik controls also - I dropped the grid on OK, but when I clicked 'Add Rad Script Manager' from the quick properties I receive the same error. 

Changing <MasterTableView ColumnSettings="(Collection)"> to <MasterTableView> worked to remove the error from designer view, but will this break the grids functionality?

Not the best start for my 30 day trial, we're deciding whether to move over from IG. What's the official recommendation until a new patch is released?

[Oleg]

Same issue, like other users pointed out it started after upgrading to the latest version of Telerik a few days ago.

[GACA]

I am also facing same issue.

[Ricardo Cáceres]

Delete the property ColumnSettings="(Collection)" from the source view.

[Dan]

I have opened a ticket with Telerik on this issue and will post the "approved" solution.  I agree with others that deleting the ColumnSettings="(Collection)" attribute from the MasterTableView source isn't necessarily the best long term option since it is unknown as to what impact that might have on other pieces of the grid's functionality.

For those of you who are looking at Telerik from IG, I was in your shoes 3 years ago after getting frustrated with IG's lack of documentation and support.  I have been very pleased with the QA on the Telerik products up until the Q1 2013 release.  This release has been very buggy and I hope it is not a sign of things to come.  I will say that the documentation and ease of use still is far superior to IG imho.

[Maria Ilieva]

Hi,

We completely understand your concerns and frustration form the presented issue. Our dev team already fixed the problem and the fix will be available in the upcoming build next week.
Excuse us for any inconvenience this issue may lead.

Regards,
Maria Ilieva
the Telerik team

[Shawn Clabough]

I get the error just by unchecking "auto-generate columns at runtime".  I cannot remove the columnsetting attribute because my entire tag is only

<telerik:RadGrid ID="rgPosts" runat="server"></telerik:RadGrid>

[Stormdude]

Agreed!

[Simon]

Yes I get exactly the same thing and there is no Collection to remove, bloody frustrating!!!!

[Maria Ilieva]

Hi,

If you make any changes in the RadGrid designer the mentioned property will appear in the RadGrid markup. Then you could remove it and fix the problem.
Note that the issue fix will be part of the upcoming SP2 which is scheduled for the end for this week.

Regards,
Maria Ilieva
the Telerik team

[Denius]

I have problem on RadGridView not show List Collection. Shows me System.Collections.Generic.List ' 1 on winforms.

How to fix it?