rylo,

Thanks for the input.
I made a slight mistake on my original post, it is column called 'Due Cal' that needs to be filtered. (row 'N')
I altered your formula to reflect this, then in U1 put in 12. After about 5 minutes, it finally filters all results above 12 but divisible by 12, whereas I want the opposite. If I put in 12, I want to view the row results for 3,6 and 12.
If I can do this simply with a modification of the formula, then perhaps I do not need a macro to run this as I will be selecting the value of U1 from a drop down cell (showing all the filter values) on another sheet. All the user has to do is select a value, say 144, and the 'All Tasks' sheet will display all the tasks for 144 and values divisible into 144.

I will try and play with the formula, but any advice would be great.

Cheers.

JD