If the Macro Security setting cannot be changed through the Access application (can be disabled in the installation), this registry setting can help.
To set the security to "Low":
[HKEY_Local_Machine\SOFTWARE\Microsoft\Office\11.0\Access\Security]
"Level"=dword:00000001
This applies to Office 2003, but similar keys exist for earlier versions. This may not apply to Office 2007 - further research needed.