can alarm be coded into a cell "x" hours before date's reached ?

[Guest]

Have spreadsheet of key dates & am looking to set up an alarm in advance of
date being reached, say 72 hours before stipulated date - is this possible
w/out knowledge of VBA

 

[Guest]

We can use condtional formatting:

Say we have a list of dates in column A and we want to hi-light those that
are coming due within the next 72 hours:

Select A1 and pull-down:

Format > Conditional Format... > Formula is

=IF((A1-NOW())<72/24,1,0) and pick a distinctive format

Then copy the format down the column.