Take out <base> tag from master page and copy it all .aspx pages and change href tag in test.aspx to href=http://localhost/testsite/test"

Thanks for the response.

What do I want to do is When the Button is Clicked, the page is postbacked to the same page ?

 Any possible help for this?  

Thanks for the response.

What do I want to do is When the Button is Clicked, the page is postbacked to the same page ?

I cannot do Response.Redirect as I have form and the lots of form datas are required to be posted and the Base HRef in Master Page cant be changed.

 Any possible help for this?  

Pasa,

In all .aspx pages that are not in root folder (testsite in your case), add action attribute to form tag with foldername/Webpage.aspx. So your test.aspx page will have form element that looks as below:

</form>

FYI:

http://www.w3.org/TR/html401/struct/links.html#h-12.4