You can use the following temporary workaround in order to avoid the problem:
1. Attach OnGridCreated event handler:
    ...
    <ClientSettings>
         <ClientEvents OnGridCreated="onGridCreated" />
    </ClientSettings>
    ...

2. In the event handler configure the group header according to the number of visible columns in the grid:
          function onGridCreated(sender, args) {
              if ($telerik.isIE7) {
                  var visibleCount = sender.get_masterTableView()._getVisibleColumnsCount();
                  $telerik.$(".rgGroupHeader .rgGroupCol + td", sender.get_element()).attr("colspan", visibleCount);
              }
          }

We are using version 2012.Q3 of Telerik, for the RadGrid control.

Once we updated to VS 2013 Update 2, we experienced a rendering problem on our development machines for all RadGrids on our site.

Upon further review we found out that this was due to the Browser Link feature in VS 2013. Browser Link appears to inject code between the development environment and the web server(s).

We were able to fix this upon finding an article pointing us towards the Browser Link feature. However it did take quite a while to figure out the issue, so we wanted to pass this along so that you could create a Knowledge Base article about this so that others can find the solution more easily and quickly.

Resolution:
Add the following item to the AppSettings section of the Web.config
<add key="vs:EnableBrowserLink" value="false" />

References:
http://weblogs.asp.net/imranbaloch/archive/2013/10/23/messy-html-and-js-errors-when-you-install-visual-studio-2013.aspx

http://stackoverflow.com/questions/19513631/radgrid-rendering-differently-in-different-machine-of-100-same-application-when

http://www.asp.net/visual-studio/overview/2013/using-browser-link 
(what is Browser Link)

RadGrid cannot edit in IE8 under 2014Q2
javascript thows errors:
URI: http://localhost/Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=RadScriptManager1_TSM&compress=1&_TSM_CombinedScripts_=%3b%3bSystem.Web.Extensions%2c+Version%3d4.0.0.0%2c+Culture%3dneutral%2c+PublicKeyToken%3d31bf3856ad364e35%3azh-CN%3a8f393b2b-3315....

To fix the upper problem, we appyied 2014Q2SP1, however, in IE8, javascript thows new errors:
“sys is undefined” 
and the RadGrid does not display in web. But this is ok in debuging mode.

I want column width state maintain on postback. here with i am attaching may aspx page

My Sort order of records is persisting in normal radgrid but when i am using radgrid with grouping its not persisting.

The ragGrid during page load are as folllows.

Customer group Name        Customer Name      Sort Order
Group 1
                                              Very High                    1
                                                High                          2
                                               ABC                           3

and the filer for columns format are as follow

<telerik:GridBoundColumn HeaderText="Customer Name" FilterControlAltText="Filter column1 column"
                                    DataField="Name" UniqueName="Name" FilterControlWidth="150px" AutoPostBackOnFilter="true"
                                    HtmlEncode="true" CurrentFilterFunction="Contains" ShowFilterIcon="false">
                                </telerik:GridBoundColumn>

And when i filter the grid on customer name with "high" word the grid shows results as follow

Customer group Name        Customer Name      Sort Order
Group 1
                                                  High                        2
                                              Very  High                   1
                                               
And i am needdatasource event then also this problem occurring so please provide me any solution.

grid line are not showing here with i am attaching the my aspx page and the current output page screen shot. this issue are randomly generated may be generate on first page load or on page scroll some lines visible or invisible. But grid line are always shown in IE8.

Hi Team,

Please go through the ticket.
http://www.telerik.com/account/support-tickets/view-ticket.aspx?threadid=821301

Here' there is javascript error on Filter click. We have attached the example in first thread.

The example contains a grid with a runtime header column addition. When the filters are on with Grid, clicking any of the filter icon to open "filter menu" causes a JavaScript error.

 If we skip the code to add "Runtime header column", there is no such error. But there is requirement of our client to have such header "Skip to Content" button in the header above filter.

Please see,
 - We are using a webcontrol, AECTelerikGrid as attached.
 - This should display "Skip to Content" in the header bar.
 - After this, click on any of the filters and this will result in JS error as attached.



Thanks,
Sunil

I am using a user control to insert and update the data found in the MasterViewTable as well as other detail items bound in child tables not included in the grid.  How does one pass the key value to the user control.  I am new to Telerik but it shouldn't be this difficult.

For reproducing this you need to set: RadGrid1.DataSource = null;

Still when DataSource = new List<object>(); is set for DataSourse the RadGrid is successfully bound and does not throw errors.

The latest update of Chrome browser Version 33.0.1750.117 breaks the radgrid vertical scrolling with these settings:

 <ClientSettings AllowColumnHide="True" AllowKeyboardNavigation="True">
                                    <Scrolling FrozenColumnsCount="1" UseStaticHeaders="True" AllowScroll="True" EnableVirtualScrollPaging="True" />
                                </ClientSettings>