An API version is required, but was not specified. webapi
var constraintResolver = new DefaultInlineConstraintResolver() { ConstraintMap = { ["apiVersion"] = typeof( ApiVersionRouteConstraint ) } }; config.MapHttpAttributeRoutes(constraintResolver); config.AddApiVersioning(o => o.AssumeDefaultVersionWhenUnspecified = true); [ApiVersion("2.05")] [RoutePrefix("api/v{version:apiVersion}/ger")] public class caGerController [Route("~/api/ger/getDetail")] [Route("getDetail")] GetGerData [ApiVersion("1")] [RoutePrefix("api/v{version:apiVersion}/gerDetail")] public class caGerDetailsController caGerController [Route("~/api/gerDetail/getDetail")] [Route(