i output cached my .aspx page for a long period of time, now i want to change some markup on the page, how can i make it invalidate its cache(make it refresh it self)?

HttpResponse.RemoveOutputCacheItem("pathtoyourfile");

it gave an error indicating that "An absolute virtual path is expected" ?

Well you will need something like:

HttpResponse.RemoveOutputCacheItem(Server.MapPath("/directory") & "file.aspx");

or just

HttpResponse.RemoveOutputCacheItem("/directory/file.aspx");

Not entirely sure, haven't used it in a while. Looong time.

Should work.. It's in C# for you too :)

Come on shesaid.. why dont you ever try the code yourself and paste it? Please give me an accurate answer

Can't, I am at work and at work I work on a linux machine and have no access to FTP connections. Therefore I cannot test anything ^^

Well a way you can do it resides in just resetting the expiration the file

Set the expiration on the file to now or now + 1 second.