Error: "Query Interface...."

[Heike]

I (unfortunately only sometimes) get the error message "QueryInterface for interface System.Runtime.InteropServices.UCOMIConnectionPoint failed".

What does that mean?

This morning I got it when debugging at the following statement:

RemoveHandler CType(objWordInstance, Word.ApplicationEvents2_Event).DocumentBeforeClose, AddressOf DocumentBeforeClose

Random?

[Toni]

I’ve the same problem. I’ve a VB.Net program using functions from a VB6 dll and sporadically I get this message. Did you find any solution or explanation?

[Heike]

Not really.
I put the statement I mentioned (Removehandler...) in a empty try...catch...end try:

Try
    RemoveHandler CType(objWordInstance, Word.ApplicationEvents2_Event).DocumentBeforeClose, AddressOf DocumentBeforeClose
Catch
End Try

and after that I didn't have the error again. But I think that's only a kind of workaround not a solution.

[Toni]

Thnx, I will try this “solution” (or workaround), if it works, it is enough for me.

[Toni]

Hi,

I’ve found a solution for this bug, (I don’t know if you exactly have the same problem) My application is using COM objects and I get this message leaving the application idle for approx. 10 or 15 min., and then trying to work with it again. Surfing the web, I’ve found that Microsoft has a patch for this bug; the patch is Q325699, but it is a non-public fix and you have to contact Product Support Services to get it (in any case, this bug will be fixed in the next framework service pack).
I’m using this patch and at the moment it works fine.