Data Validation with fool-proof system

[Sundarvlr]

Hi All,

I am new to the forum, starting learning excel from this forum it is very helpful. Thanks for effort to help others.

Now i have a question in using Data validation tool. Please find the attachment.

Need to allocate batch no's 1 - 8 for the eight pupil for that i need a fool-proof system which will not allow to allot same number to other persons.

[popipipo]

Take a look at this.

[Sundarvlr]

Thats Great, Its works for me.
Thanks for your help....