ASP

Header

301 Moved Permanently

永久性重新定址

Response.Status="301 Moved Permanently"

you may set up a default error page which content 
the 301 permanent redirect method

Response.AddHeader "Location", URI path

basic 301 can be a way to avoid  404 error message page appear

將(錯誤訊息頁)設定Response.AddHeader 
301 Redirect 主要目的為
永久性重新定址
改變網址而不會出現「404 找不到網頁」