Consider moving this over to MS-Access and turn the workbooks into relational
tables. You can then set field level validation.

_ PJK _

"madbloke" wrote:


I have an excel file with multiple workbooks (month by month) which,
amongst other things, contains reference number and name (columns C &
D).

When entering these details, I'd like it to check across all previous
entries (and previous months) for an exact match, and if it finds one,
to pop up a messagebox asking if it's ok to enter a duplicate.

I was thinking along the lines of a VLOOKUP formula, but that would get
overwritten when entering the data, so I'm stumped.

Any ideas?


--
madbloke
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