Field expression formulas

[joebordes]

Try putting the sum directly, eliminate the equal sign

Code:

cf_696 + cf_698 + cf_700

note that this is execute on the save event, not when loading the edit screen

Also, please use the workflow update field task, Field formulas are obsolete, workflows are more powerful and will keep getting bug fixes and enhancements while field formulas will be left there as it is only for backword compatibility.