System.InvalidCastException: QueryInterface for interface

Posted on 2003-03-03
Medium Priority
Last Modified: 2013-11-18
I have a managed code that is calling unmanaged Com+ vb6 code , I always get this error for 1 component , other are working ok:
This component used to work ok..
One fact is that this is a webfarm cluster on several machines we are having the same problem
I traced the error on the web and it says (the closest) that this error might be due to threading conflicts (the unmanaged component is running in single app mode) but I repeat this used to work!

any clues?
Question by:Silvers5
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Expert Comment

ID: 8056561
I am assuming that you ae invoking your invoking unmanaged serviced  componenet from web form...
I Am asure you must have tried this.. but let me ask. Did you try setting aspCompat attribute to put ASP.Net thread as STA because all VB6 components are STAs.
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Author Comment

ID: 8690124
yes it is set in the directive to true
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Accepted Solution

Silvers5 earned 0 total points
ID: 9201718
Hi.. the thing is that i upgrade to Application center 2k sp2 and it worked.. it seems Application center sp1 never replicated the gac..

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