Hi Lucy,
just one thing to consider:
Formulas in local members have to be entered in english format, independent of your application language. However, formulas in diffenrent languages and commands wont work.
An example:
If your language in Excel (Application Language) is German and you put as formula =SUMME(A1:B1) into the local member, you'll get the error message as in your case. You have to enter =SUM(A1:B1) and it will work fine.
Hope, this will help you,
Karsten