caching in aspnet

I'm trying to do server caching for some pages of a
website I developed.

All the pages include the same user control to which they pass a parameter.
In this user control I have the following 4 lines.

Response.Cache.SetValidUntilExpires(true);
Response.Cache.SetCacheability(HttpCacheability.Server);
Response.Cache.SetExpires(DateTime.Now.AddDays(7));
Response.Cache.VaryByParams["cat"] = true;

When I go to the website through localhost on the server
the caching seems to work, however when i try to access
the pages from anywhere else the load time is the same
(slow) every time i refresh the page.

any help would be appreciated

thanks

-Evgeny


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