Mark,

You have found the perennial problem with MsgBox in a function , they pop-up
all the time, even when you don't want them.

How about a design change, rather than use a MsgBox, use Conditional
Formatting.

Select all of the cells with this formula, say starting in row 4, and goto
CF (FormatConditional Formatting), change the condition to Formula Is, add
a formula of =(F4-E4)=15, and click Format, select Pattern, and choose a
colour.

You will then see all items overdue in colour. Not affected by autofilter.

--

HTH

RP
(remove nothere from the email address if mailing direct)


"Mark" wrote in message
...
Hi
I have a worksheet made up for different cost centers
with reference to invoices. For example who they are
from, what date is on the invoice, what date did we
receive it, amount, etc. I have written the following
module and formula (see below for details) in order to
bring up a message box if the amount of days between two
dates are greater than 15. The reason for this is that we
have a turnaround time of 14 days to pay these invoices
and staff forget to issue a late letter if the invoice is
paid outside the 15 days.
This works great, the message box appears when the days
are greater than 15 days, the only problem is when you
run auto filter the message box will appear again before
searching under filter.
Can I add something to the module (see below) to stop the
message box running again when you click ok
As you are probably aware I am a novice and any help
would be greatly appreciated

Module
Option Explicit

Public Function PromptPayment()
MsgBox "Please issue Prompt Payment Letter and input
relevant information to PP spreadsheet"

End Function

Formula
=IF((F4-E4)=15,PromptPayment()+F4-E4,F4-E4)

Thanks Again