xlsm file that is saved on Windows 7 platform crashes when opened on Windows XP platform

Our company is in the process of converting over to Windows 7. One person, Ann, on my team is running on Windows 7 and the rest of us are on Windows XP. We all are using Excel 2007. We all use the same template for this file as well. But when Ann saves the xlsm file the rest of the group is unable to open her file. It crashes Excel completely and you have to re-open the program. We put Ann's Office programs in compatability mode which we thought would fix the issue, but it hasn't.

I have scoured the internet and Excel forums looking to see if anyone else has had this problem and I have come up empty.
We are ready to re-image her computer back to XP, but would like to see if there is a setting we can change to make this work.

Could it have anything to do with Ann using a 64-bit version of Excel/Office and everyone else using a 32-bit version? Just wondering... it's the first thing that popped into my head. For all I know, Ann's version is also 32-bit.

- Moo

I just checked and yes Ann is running 64 bit and the rest of the team is still 32. Do you think this is the problem then?

It's certainly a possibility. From what I have had the chance to read, there have been 'issues'. One sure way to tell... uninstall her 64-bit version of Office and install the 32-bit version.

- Moo