When i tried to attach a file in custom list form(CustomNewForm.aspx) i got an error message :“This form was customized not working with attachment”
This is a know issue. here is a smart workaround for this
- Download and install Infrastructure Update for Windows SharePoint Services 3.0 (KB951695)
- Then follow this article http://support.microsoft.com/kb/953271
- Voila! it works fine for me.