Prevent UDF from calculating when opening file
 

Hi,

I have created some User Defined Functions, which take a value from a
Access-database. Users have to log in into the database by a vb-login
screen. After loggin in they can get the values from Access. This is working
fine, but...

When I open the sheet, Excel always recalculates all functions, including de
UDF's. Because the user is not logged into the Access-database all results
are set to zero. Is there way to prevent the UDF's from recalcuting when
opening the sheet? I don't mean to set the calculating to Manual, but I mean
a programmatically way to keep the old values in the cells without
recalculating them.

Gr. Arie