Really strange, you might want to post a forum/ticket for RadControls for Windows forms to see if they know anything about this behavior.
As for the original problem, I forgot to ask what Visual Studio version you use and whether the Report Items
are available in your Toolbox or they are missing as well? If they are not I suggest you verify the installation by checking whether the "new item" templates are placed in (for Visual Studio 2010):
C:\Program Files\Microsoft Visual Studio 10.0\Common7\IDE\ItemTemplates\CSharp
and C:\Program Files\Microsoft Visual Studio 10.0\Common7\IDE\ItemTemplates\VisualBasic\Reporting
i.e it should contain a file named Telerik_Reporting_Q2_2010_SP1.zip.
If it is missing, the easiest way to recover the installation is try repairing the product installation.
Another possibility is deselecting Visual Studio support during Telerik Reporting install, which in your particular case is not, since you had the items initially. Also if you are under Vista or Windows 7, you must start
the installer as administrator, otherwise it might produce such quirks.
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