IE6 slow when going to some SSL sites through proxy server

[Todd Michael Bushnell]

My customers are experiencing problems when connecting to
our web application through a proxy server. Our web
application does run over SSL, but the common denominator
for those with problems is a proxy server - sometimes
Microsoft ISA, sometimes other vendors running on MS
operating system.

There was a patch that I discovered about year ago
(q331906) that provided significant improvements for
customers having problems at the time, however this patch
will not install on newly updated versions of IE6 due to
older DLL versions. I would like to think that MS has
since ensured that this patch is part of new versions of
IE, but I can never be sure.

I've done a number of tcpdumps and notice a unusually high
amount of client initated tcp resets which would explain
the slow performance as the tcp and ssl sessions would
need to be renegotiated. Unfortunately, I'm not sure what
could be causing the problem and don't know what to do
next short of requesting my customers relax their security
profiles by bypassing their proxy for connections to our
webapp. Any suggestions would be appreciated.

 

[Robert Aldwinckle]

My customers are experiencing problems when connecting to
our web application through a proxy server. Our web
application does run over SSL, but the common denominator
for those with problems is a proxy server - sometimes
Microsoft ISA, sometimes other vendors running on MS
operating system.

There was a patch that I discovered about year ago
(q331906) that provided significant improvements for
customers having problems at the time, however this patch
will not install on newly updated versions of IE6 due to
older DLL versions. I would like to think that MS has
since ensured that this patch is part of new versions of
IE, but I can never be sure.

Sometimes when hotfixes which involve changes in functionality
are integrated into the commonly distributed modules they have
to be implemented with registry switches which have a default
value which means: "hotfix off". Absence of the registry value
usually implies that its default is to be used.

I would try using RegMon to see if the new distributed wininet.dll
is testing for the existence of any registry values which look as if
it might provide such a switch. E.g. start roughly by using an
input filter of iexplore.exe*NOTFOUND


Good luck

Robert Aldwinckle
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