How to prevent double entry in excel?

G

George Teng

Hi,

I'm trying to avoid double entry in this particular work here. Is there any
formulas or function that allow me to automatically detect the double entry?

George
 
B

Biff

Hi!

You can use Data Validation to do this.

Assume you'll be entering data in the range A1:A100 and
want to prevent any duplicate entries.

Select the range A1:A100
Goto Data>Validation
From the Allow drop down select Custom
In the Formula box enter:

=COUNTIF($A$1:$A$100,$A1)<=1

If you want, you can create a custom message that will pop
up if a duplicate entry is attempted.

Click the Error Alert tab.

Use a message something like this:

You are attempting to make an entry that already exsists!

Click OK and you're all set!

Biff
 
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