Prevent duplicate entires in Excel

[aprunkard]

Is there a way to prevent duplicate entries in a column in Excel? I know how to find duplicates, but I want to prevent them. I'm looking to use this in a spreadsheet that will be used to keep the VIN numbers of vehicles in stock.
Thanks!

 

[carrr]

Have a look here:

http://www.mrexcel.com/tip008.shtml

or here:

http://www.theexceladdict.com/_t/t040818.htm

Tired of waiting for an answer? Try asking better questions. See: faq222-2244

 

[DaleWatson123321]

The only thing I would add is...

1) Select the Entire column by clicking the column letter.

2) Use this slight modification to the Data Validation formula...

=ISNA(VLOOKUP(A1,A:A,1,FALSE))


Regards, Dale Watson

 

[SkipVought]

You can do this with Data/Validation - Custom and entering a formula like this...

assuming that your data entry range is A2:A10

then...

select A3:A10
Data/Validation - Custom
[tt]
=AND(A3<>$A4:$A$10,A3<>$A$2:A2)
[/tt]
A2 contains
[tt]
=A2<>$A$3:$A$10
[/tt]


Skip,

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