I'm using the following formula to give a value to several items of data
that I want to link into a Visualbasic program:

=IF((AND($U$1=Y2,Z2="D")),1,0), where $U$1 is the copy of a date in U2 (set
up as a relative link to another spreadsheet.

However, when I run a macro to copy the date in U2
(as either values or values and number formats) into U1 the formula does not
update in the row where the condition is met.

Why does it not update and how can I solve this problem?

Many thanks