OLE or Active X errors running Macros

[FMC]

I have not done any work in Access for some time. I just created a new
database using Access 2003. Why do the Macros I'm creating cause errors ( OLE
or Active X) and work fine on older PC's using Office 2000? Even Older
databases with macros run fine causing no errors in 2003. If I copy the
create the same Macro in the new database I get the errors ( OLE or Active X)
every time.

Thanks in advance!