[thelist] Internet Explorer 6 generating many duplicate hits

[Gijs van Tulder]

Hi all,

I'm having a problem with Internet Explorer 6, which according to my
log files sometimes generates many duplicate requests in a very short
period of time.

On two different sites, one is PHP on Apache, the other is Ruby on
Rails on Apache+mod_proxy+lighttpd, it regularly happens that a
request is repeated again and again and again, many times per second.
This happens with normal GET and POST requests as well as with
xmlHttpRequest POST requests. The whole request is exactly the same
each time: same host, same url, same POST data, same referer, same
browser. The browser is always MSIE 6.0 (on various platforms, WinXP,
2000, NT4.0, 98 etc.).


I have found one report of a somewhat similar problem:
 http://groups.google.nl/group/nz.comp/browse_thread/thread/499a490565b69e56/0ba8e135cf59f8fd

But that discussion is for IE 4&5 (my problem only occurs with IE6),
his requests do not have a referer (mine do), and all his requests are
for the root url (my requests are for many different urls).

The requests come too fast to be caused by the user clicking buttons or links.

It doesn't happen often, most of the time the site works correctly
(even for the problematic clients before they suddenly start sending
duplicate requests). I haven't been able to reproduce the problem
myself, I only know it from the logs.

For the xmlHttpRequest, a Javascript error could in theory be the
cause of this problem, but I use the standard Prototype library, so
that shouldn't be the problem. Besides, even normal GET requests (the
result of the user clicking a perfectly normal link) are duplicated.


I don't have a clue as to what I can do about this. Does anyone have
an idea what this could be?

Thanks,

Gijs


A few typical lines of the logfile (note: it's not always exactly this
user-agent string, but it always includes MSIE 6.0):

145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
145.97.34.132 www.___.nl - [17/Jan/2006:09:24:44 +0100] "POST
/user/login HTTP/1.1" 200 4493 "http://www.___.nl/user/login"
"Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"