Not allow entering repeated references in a column - HOW?

[ritinha]

Hi Frank,
- BEFORE entering the formula in the data validation dialog, I´v
selected the cells from A1 to A25
- which values? well ... I´ve tried numbers (2,3, ..) just to certif
if it was working ... & once I´ve typed the first number ... the erro
message appeared.

Thanks for your time,
Ritinh

 

[Frank Kabel]

Hi
if you like email me your file and I'll have a look at it