Problem Including Files From Different Directory

I'm trying to include and calling some ASP files from different directory. It doesn't work.

I need to use <A HREF>tag to link the ASP file and image file using <img src>tag. I entered the whole http://mydomain.com/....... path inside of tag. It doesn't work.

For example.

The original web page is reside in c:webrootwebpageestpagehomepage.asp

All the image files and other ASP files are reside in:

c:webrootwebpageaspfile.asp
c:webrootwebpageimagefile.jpg

In the IE browser, the link would go to
http://www.mydomain.com/webroot/webpage/testpage/aspfile.asp

Of course, it won't work because the aspfile.asp is reside in webrootwebpage, NOT in webrootwebpage estpage diretory.