Enabling macros in Excel 2000-2004 is straight forward - at least more straight forward than in Excel 2007-2010.
There are two steps:
First, make sure your global Macro Security is set to Medium. This only has to be done once and the Medium setting will be remembered when you close and open Excel and/or if you shutdown and restart your computer.
Second, with the setting on Medium, you will greeted with a prompt to Enable Macros each time you open a workbook that contains macros. If you trust the author then click Enable Macros.
This is a security feature that stops malicious macros from automatically running when the file is opened. Leaving the setting at Low will allow any macro to run without a security prompt. Malicious macros can erase or corrupt your drives and files and can access private information.
1) Set Macro-Security to Medium. This only has to be done once and will be set for all files.>
2) Enable Macros