You'll want to make sure that you don't use any new functions such as
IFERROR, SUMIFS, etc. If possible, can you save the workbook as XL 2003 file
type?

The name change occured because in 2007, APR09 is a possible cell reference.
Thus, XL added the underscore in front of the name for clarity.

--
Best Regards,

Luke M
"WLMPilot" wrote in message
...
I have been writing macros and utilizing userforms in Excel to use at work.
I am doing this on my personal computer and I am about 95% complete. I
was
using pre-MS Office 2007. Work also utilizes pre-MS Office 2007.
However, I
have upgraded both my personal computers to MS Office Enterprise 2007.

I am not using any complex macros. Basically, simple calculations, Date &
Time commands, and cell references (Range, Offset, etc). I did notice
with
one of my personal workbooks that the NAME for the cell I used, "APR09",
had
to be changed to "_APR09" (without quotes), in the 2007 edition of Office.

The two questions I have a
1) What do I need to do in order to ensure compatibility with the pre-2007
version
at work?
2) Why did the underscore have to be added to the cell name?

Thanks,
Les