Question : Syntax, subforms, multiply 2 fields

I am having difficulty with multiplying two fields.  [txtContractAmount] * [txtPercent]
The form "Project Details" is tabbed
There is a subform with name of "Project Details_Page" (dont know if this is impt)
txtContractAmount is not contained in a subform but rather on the tab entitled "Project Details_Page"
"frmMilestones" is a subform on form "Project Details"

=([Project Details].[Form]![txtContractAmount])*([Project Details].[Form]![frmMileStones].[txtPercent])

(I also need it to handle Nz)

Thank you

Answer : Syntax, subforms, multiply 2 fields

1) can you try going to admin, tools, clean cache?

2) are you positive mod_rewrite is working?
to test add this line to the top of .htaccess, your site should go to google:
RewriteRule (.*) http://www.google.com

3) how about SEF withOUT .htaccess (after trying the other two above first)