Telerik ASP.NET Prometheus & VS2008: could not load assembly

When creating a new website in VS2008 I had an error to load the r.a.d.grid component in the designer. The error said something about 'Could not load the assembly Telerik.Web.UI.dll'

Turns out that e.g. r.a.d.grid uses the 'Telerik.Web.Design.dll' for the designer. Problem now is that since VS2008 has multiple targets (frameworks), there are also 2 versions of the 'Telerik.Web.Design.dll'. After some searching I discovered that the version of the designer that is made for .NET 3.5 couldn't find the 'Telerik.Web.UI.dll' inside the GAC. So, if you do not have problems installing this .dll into the GAC, then you should give it a try!

Install the 'Telerik.Web.UI.dll' into the GAC (Global Assembly Cache)

  1. Use the VS 2008 Command Prompt. If running Vista, right click the icon and run the tool as an administrator.
    This will get the directory for the gacutil program into the path statement.
    (You could add this directory to your PATH variables inside your computer settings)
  2. gacutil /i "C:\Program Files\Telerik\RadControls 'Prometheus' for ASPNET Q3 2007\Bin35\Telerik.Web.UI.dll"

After this, you should be able to see the r.a.d.controls in design mode!

door Daniel Plomp


RadEditor - HTML WYSIWYG Editor. MS Word-like content editing experience thanks to a rich set of formatting tools, dropdowns, dialogs, system modules and built-in spell-check.
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