Issues with in try except and excel spreadsheet

[padawanwebdev at gmail.com]

Hello, I'm having a problem with a try except inside a while loop. The problem I see occuring has to do with an excel file the script tries to write to while the excel file is open. The exception captures and gives an error:

OError: [Errno 13] Permission denied:'C:\\Users\\Administrator\\Desktop\\Version5.0\\DeviceTrackerReport45.xlsx'

This is expected and is not the problem. However, the issue occurs when I close the excel file. As an example, if I run the script and the excel file is open thru 3 iterations, meaning that the script can't write to the excel file until the excel file is closed, then after the excel file is closed the script prints to the excel file 3 times. I don't need it to write to the excel file 3 times. I only need it to write just once. If the excel file is closed before I run the script than it works like its suppose too. 
I hope I made my case clear. I look forward to some feedback. Any would be greatly appreciated!  

here is part of the code:
        
        connectionResults = None
        returnResults = InternetQualityTest.connectionTest(connectionResults)
        if returnResults == True:
            try:
                execfile('assetMapping.py')
                time.sleep(4)
                sys.exit()
            except Exception as e:
                print "error",e
                time.sleep(20)

FYI: The assetMapping.py runs another module from inside, and it's this module running from assetMapping that writes to the excel file.