Validations in excel for particular column

[Guest]

In one of the column the same data should not be repeated while entering or
coping and should prompt or give a error message. OR

How can i ensure that the same data is not repeated while entering or coping
in a particular column? Pl help.

 

[Guest]

One way, assuming data will be only* be entered manually down col A ..
*as any copy-pasting, or dragging down a cell with input in it will override
the validation

Select col A (click on the col header "A")
Click Data > Validation
Allow: Custom
Formula: =COUNTIF($A:$A,A1)<2
Click OK

Test it out ..

 

[Max]

1st line should read as:

One way, assuming data will only* be entered manually down col A ..

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[Guest]

Thank you for your reply. You have solved one problem but another is still
unresolved.... copy and pasting from other file if with any command can be
restircted nothing like it..

 

[Guest]

Pl see my response to your new posting ..
(an example using worksheet code by Vasant)