Excel found unreadable content

[Greg Creme]

I am creating a workbook through a program that I created, consisting of
multiple worksheets that are fairly basic and have formulas in them to sum
up the contents of cells.

first my question: I am trying to find out how to troubleshoot this problem
and view the details on what cell or cells has an error in the workbook that
I am creating.

Now all the long, drawn out details:

When the excel sheet is saved by the program, when I try to open it up in
excel 2007, I get a message that says:

__________________________________________
Excel found unreadable content in 'FileName.xlsx'. do you want to recover
the contents of this workbook? If you trust the source of the workbook,
click Yes.
__________________________________________

If I click no, the workbook closes. When I click yes, I next get the
message that says the following:

__________________________________________
this file cannot be opened by using Microsoft Excel. Do you want to search
the Microsoft Office Online Website for a converter than can open the file?
__________________________________________

Clicking yes opens excel, but with no file. clicking no, excel proceeds to
open the file with yet one more message.

__________________________________________
Excel completed the file level validation and repair. Some parts of the
workbook have been repaired or discarded.
__________________________________________

There is a link for an xml file that says has details on the validation and
repair, but the file only contains the following:

<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
- <recoveryLog
xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main">
<logFileName>error039440_01.xml</logFileName>
<summary>Errors were detected in file 'C:\Documents and Settings\gregc\My
Documents\WarehouseInventory.xlsx'</summary>
- <additionalInfo>
<info>Excel completed file level validation and repair. Some parts of this
workbook may have been repaired or discarded.</info>
</additionalInfo>
</recoveryLog>

These details are not very useful for me to be able to figure out what I am
doing wrong that is causing this message. Can anyone point me in the right
direction for how to troubleshoot this problem and figure out where the
problem lies?

Thanks for your help!