Avoiding Duplicates

[Guest]

I would like to apply Data Validation to entries in a cell to prevent
duplicates, but I need the facility to enter a "valid duplicate" eg When
entering a surname that has been used before a warning is returned but this
can be ignored if entry is valid.

 

[VBA Noob]

Hi,

say your area is A1 to C20. Select it go to Data Validation and enter.

=COUNTIF($A$1:$C$20,A1)=1

VBA Noob

 

[Bob Phillips]

Use a formula of

=COUNTIF($A$2:$A$209,A2)>1

where A2 is the DV cell, and on the Error Alerttab of DV, set the error
style type to Warning

--

HTH

Bob Phillips

(replace xxxx in the email address with gmail if mailing direct)

 

[Bob Phillips]

Sorry, should be = 1

--

HTH

Bob Phillips

(replace xxxx in the email address with gmail if mailing direct)

 

[Guest]

Thanks Had done formula correct but not altered Error Alert tab works fine