Hi

I created an invoicing system that uses Vlook-up in Excel.  The Excel
worksheet has a drop down menu and when the user clicks on it, they
get a list of company names that they can select from. Selecting a
company name automatically fills in the name and address fields on the
invoice.

In the past, the name and address would automatically appear when you
select the company name from the drop down menu.
However, recently, it will only appear when you save the book.

The same problem happens with auto-sum.
In the past, the auto sum cell would automatically update as you
changed the values in the cells that it related to.
However, now the auto sum cell only updates when you press save.

Is there a solution to this problem?

I am using Excel X for mac.