Commented Issue: Error with MaskedEditValidator [26984]

When i try to use the MaskedEditValidator I get a NullReferenceException

That is the Call stack location

AjaxControlToolkit.DLL!AjaxControlToolkit.MaskedEditValidator.OnPreRender(System.EventArgs e ) Line 360 + 0X29 bytes

and Source file information:

Locating source for 'C:\Users\Stephen\Documents\Repos\Superexpert\AjaxControlToolkit\Server\AjaxControlToolkit\MaskedEdit\MaskedEditValidator.cs'. Checksum: MD5 {ea 2f 74 58 2f 82 7f 77 98 d9 88 ba c4 e0 18 25}
The file 'C:\Users\Stephen\Documents\Repos\Superexpert\AjaxControlToolkit\Server\AjaxControlToolkit\MaskedEdit\MaskedEditValidator.cs' does not exist.
Looking in script documents for 'C:\Users\Stephen\Documents\Repos\Superexpert\AjaxControlToolkit\Server\AjaxControlToolkit\MaskedEdit\MaskedEditValidator.cs'...
Looking in the projects for 'C:\Users\Stephen\Documents\Repos\Superexpert\AjaxControlToolkit\Server\AjaxControlToolkit\MaskedEdit\MaskedEditValidator.cs'.
The file was not found in a project.
Looking in directory 'C:\Program Files\Microsoft Visual Studio 10.0\VC\crt\src\'...
Looking in directory 'C:\Program Files\Microsoft Visual Studio 10.0\VC\atlmfc\src\mfc\'...
Looking in directory 'C:\Program Files\Microsoft Visual Studio 10.0\VC\atlmfc\src\atl\'...
Looking in directory 'C:\Program Files\Microsoft Visual Studio 10.0\VC\atlmfc\include\'...
The debug source files settings for the active solution indicate that the debugger will not ask the user to find the file: C:\Users\Stephen\Documents\Repos\Superexpert\AjaxControlToolkit\Server\AjaxControlToolkit\MaskedEdit\MaskedEditValidator.cs.
The debugger could not locate the source file 'C:\Users\Stephen\Documents\Repos\Superexpert\AjaxControlToolkit\Server\AjaxControlToolkit\MaskedEdit\MaskedEditValidator.cs'.
Comments: I am having this error too and I have not found a solution that is valid yet. This is a source code error and the "experts keep wanting to resolve this either in Web Config or to make sure that you have AJAX installed. If the tool is available to use at this point it would seem like a logical conclusion that it is also installed.