How to close a write to file express VI

Hi, 
I am using an Write to File express VI inside a subVI in LabVIEW 7.1.  Since it is in a DAQ loop it is configured to create only one file even though it is called many times. 
The problem I am having is that when the subVI itself is closed and reopened the express VI does not prompt to create a new file.  Is there a way to get around this? 
I am hoping there is some sort of invoke or property node that I can use on either the express VI or the subVI itself to close or "reset" it.
Does a subVI stay in memory even after the front panel is closed?  I am guessing this is what is causing my problem.  Any ideas?
I do realize the BEST thing to do here would be to simply not use an express VI but I am hoping there is a way to fix this without going that far yet.  From what I can tell LV7.1 does not allow me to convert an express VI to code which makes it look like it will take even longer to rewrite this.
For now the solution we have in place is the following:  close the subVI, close the main program (the calling VI), and then reload.  
Thanks,
Dave

dave,
if i remeber correcty... there is a file path option will be available with the express vi... I actualy can not reproduce this here since i dont have LV 7.1. So if you feel that the express vi does not gives you a prompt for selecting the file path, then just place a "File dialog" function before the express vi and wire the selected path.
Regards
Guru (CLA)

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