In a text box on a form, users enter how many billable minutes there are. The company I work for only bills the clients in 15 minute intervals (e.g. if the job takes 8 minutes, the clients are stilled billed for 15 minutes, if the job takes 16 minutes the clients are billed for 30 minutes, etc.). The users are supposed to already know that they are only supposed to enter multiples of 15 in the text box, but occasionally they forget and enter the actual amount of minutes it took to complete the job, instead of the billable minutes it took to complete a job. What I need to do is figure out a way to check if the value they enter is a multiple of 15 (e.g. 15, 30, 45, etc.). If it isn't I need to display and error message. I know how to create the message box, but can someone figure out how I should check if the number is a multiple of 15?

Thanks

on the beforeUpdate event of the hours

IF hours Mod 15>0 then
msgbox "Please enter BILLABLE hours in multiples of 15."
cancel=true
endif