MSComDlg.ICommonDialog Problem with Windows 64-bit system

Hi all!
I try to use the common Windows dialog box for saving files. For this I'm using the ActiveX-class "MSComDlg.ICommonDialog" with the propertynode input "Filter" for the file types. It's the standard "" (somewhere in the forum).
Everything works fine on a 32-bit Windows system. But when I run the code on a 64-bit system I can not save my file with the last file-extension in the box field. I always get a error-message: "The file name is invalid!" This happens only when the last box-element is selected. All other run normal.
So for example:
If may box array is
Matlab Files (*.mat)|*.mat
Text Files (*.txt)|*.txt
Excel Files (*.xls)|*.xls
and I select to save as *.xls and write as filename "Hello" in, I get on the 64-bit machine the error:
The file name is invalid"
When I change the order of the box array *.xls will go but the new last element will produce this error.
So, can someone help me?
Kind regards,
P.S. I'm using Win 7 64bit with labview 9 32bit. exe tested on win7 64 bit and win xp 32 bit.

Im using win 7 64bit. I'm able to register the comdlg32.ocx now but can't use it in labview. There are always error messages.
Which one do you use (see screenshots)
comdlg1.gif ‏38 KB
comdlg2.gif ‏37 KB