In your case you could update the references only manually.
Here are the steps:
1. Open the web site in Visual Studio 2008 and go to Solution Explorer.
2. Delete all files under the Bin folder.
3. Right click on the Bin folder, select Add Reference... and in the Add Reference window select the Browse tab.
4. Navigate to the dll files you want to add and press OK.
You could also use our Upgrade Wizard which is part of our Visual Studio Extensions which are distributed with the newer versions of RadControls for ASPNET AJAX. In order to use the Extensions you should download the latest Automatic Installation and install it. This you will install the Visual Studio Extensions and will be able to use the Upgrade Wizard in Visual Studio 2008.
Here are the steps for downloading the installer:
1. Log into our web site.
2. Go to You Account -> Products & Subscriptions -> RadControls for ASP.NET AJAX.
3. Click 'Download installer and other resources'.
4. Choose product and click 'Browse all product files'.
5. Download the Automatic Installation (msi) file.
Let me know if you have any further questions.
All the best,
the Telerik team
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