Help with Python COM Type Mismatch

[Markus Wankus]

Hello all,

I am having some problems with some methods in an application I am talking 
to through pythoncom, and I was wondering if anyone here was an expert and 
could perhaps give me a list of things to try (as I am not familiar with 
COM).

I am using the gencache.EnsureModule() with the CSLID makepy gave me for my 
application.  I connected to my app fine, and called a couple methods 
without any problems.  However, the third method I tried to execute has the 
following prototype:

retval = object.Method(filename, filetype, &Error)

Where filename is a string, filetype is a long integer, and Error is an 
output (long) indicating a variable to hold the error code of the method.

If I call it as follows:

a, b = Method(filename, filetype)

...it tells me The last argument is not optional.

If I call it as follows:

a = Method(filename, filetype, var)

No matter what I pass into var (I have tried pythoncom.Empty) I get an 
exception with a 'Type mismatch' on the last argument.  Is this common?  Is 
there a set bunch of steps to try to get around this problem?  BTW - 
pythoncom.Missing gives me the 'argument is not optional' message.  Also, 
certain objects (like dictionaries) give me a message that the argument 
could not be converted to COM VARIANT, so it is obviously trying to do a 
conversion.

As a side note, I still have methods with no arguments which I must call 
without brackets.  For example:

object.GetPathName() retuns an error saying 'unicode value is not 
callable', but if I just use object.GetPathName it works fine (executes the 
method and returns a string).  I thought the gencache and early bindings 
were supposed to fix this issue as well?

Anyway, I am a bit lost as I have never used COM before.  Any help anyone 
could provide would be greatly appreciated.

Thanks,
-- 
Markus