Hi,
I have had similar problems by using the fully qualified context.
the Following worked out better, since the HttpCOntext is inherited by the system.web i just use the Request.ApplicationPath, now the problem with that is that it will only return the root of where you are so if you are in "http://localhost/" it will only return "/", the fix that i found is to use the Request.CurrentExecutionFilePath, which return the entire path of the current file location, and all i need to do is then strip out the file name from the last "/". Works everytime.
Vincent Blain
Sr. Developer
Infolink Screening Services INC
9201 Oakdale Ave, Suite 100
Chatsworth, CA 91311
800-990-4473 x 1241