Could not load file or assembly AjaxControlToolkit

Error:
Could not load file or assembly 'AjaxControlToolkit' or one of its dependencies. The parameter is incorrect.

Solution:
Delete all files from:

• C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files (see all other .Net versions)
• C:\Users\[your username]\AppData\Local\Temp\Temporary ASP.NET Files

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