Hi, have you tried on of these
'RouteTable.Routes.RouteExistingFiles = False
'routeCollection.Ignore("css/{*pathInfo}")
'routeCollection.Ignore("{resource}.css/{*pathInfo}")
routeCollection.Ignore("{resource}.axd/{*pathInfo}")
'routeCollection.Ignore("{resource}.jpg/{*pathInfo}")
'routeCollection.Ignore("{*allaspx}", New With {.allaspx = ".*\.aspx(/.*)?"})
'routeCollection.Ignore("{file}.js")
'routeCollection.Ignore("{file}.css")
'routeCollection.Ignore("{file}.png")
'routeCollection.Ignore("{*alljs}", New With {.alljs = ".*\.js(/.*)?"})
'routeCollection.Ignore("{folder}/{*pathInfo}", New With {.folder = "css"})