My office application is really slow on Windows XP!

First, some backgroud stuff.

The MSAccess system that we use was developed while using Windows
2000, and Office 2000. At our new location, we are using office 2003
and XP. I did not convert the database to 2003 since a few of our
staff have laptops with windows 2000.

I have quite a few functions/macros in MSAccess that outputs to ms
excel, and I am finding that running my program on an XP machine, a
function that used to take 5 seconds, literally can take upwards to
5-10 minutes. If I choose to show excel, I can see the sheet beeing
populated very slowly, like a cell every couple of seconds. If I run
the same on the windows 2000 machine, it runs as it should. It seems
like it is a very slow communication between both programs.

I just received a call from an other office, and they just went
through the XP conversion, and they are experiencing the same symptoms
on a similar Office Automation Application they developed a few years
ago.

I have no idea as to what could be causing this problem.

Thanks in advance.
Sylvain