Test Scenerio

Tools usage for the Test

ASP.NET Web Application
.Net Framework 1.1
Windows XP
LocalHost
Fiddler HTTP Debugger
Internet Explorer

The web project also contains few JS files and Images. The application when
run through the

Internet Explorer, on local host, was not downloading few of the images and
js files on the

first case and secondly, few files were being downloaded on a subsequent
request ( here i

mean referred by other pages).

The tests were conducted first time by clearing the IE Cache (tempry folder)
and next just

refreshing IE. When looked through the Fiddler, i found :

Issue 1. (IE's cache is cleared)

Rarely and randomly few of the files are returned by server as bad
request(202). When the

same file is requested through Fiddler, the files are served properly (200).
The Headers

were proper.
On repeat request of the same application url in browser, the error may
occur again

(randomly)
with completely different file(s) (i.e the 500 error - Bad Response).

Y does this happen? Could it be because each resource request to the server
is created on

the
seperate "thread" and hence IIS is swamped with "requests" and returns a 202
for some?

Issue 2. (IE is simply refreshed - using F5)

Most of the files' response contained 304, Not Modified - which is correct
since the

If-Modified-Since
in the request header is = the Last-Modified on the file itself.

Few files which are downloading (we are facing an issue with some .js file(1
or 2) while

most other are correctly returning the 304 response ). For the ones where is
does not

return a 304 response, but instead a 200 - i.e its downloading the resource
form the IIS -

we noted that strangely the request header does not contain an
"If-Modified-Since" while

other resources with the same extension (i.e for example .js) do contain the

"If-Modified-Since" are we are correctly getting a 304 for them. How is the
client browser

(IE 6.0) seletively not sending the "If-Modified-Since" header for these (2
or 3) files

while doing it for the others? Any ideas? Anything to do with the physical
file attributes

in the application folder?

Any details on the above issues will be greatly appreciated.