Getting "A potentially dangerous Request.Path value was detected from the client (&)"

While you could try these settings in config file

<system.web>
    <httpRuntime requestPathInvalidCharacters="" requestValidationMode="2.0" />
    <pages validateRequest="false" />
</system.web>

I would avoid using characters like '&' in URL path replacing them with underscores.

I have faced this type of error. to call a function from the razor.

public ActionResult EditorAjax(int id, int? jobId, string type = ""){}

solved that by changing the line

from

<a href="/ScreeningQuestion/EditorAjax/5&jobId=2&type=additional" /> 

to

<a href="/ScreeningQuestion/EditorAjax/?id=5&jobId=2&type=additional" />

where my route.config is

routes.MapRoute(
            "Default", // Route name
            "{controller}/{action}/{id}", // URL with parameters
            new { controller = "Home", action = "Index", id = UrlParameter.Optional }, new string[] { "RPMS.Controllers" } // Parameter defaults
        );