Randbetween does not generate unique random numbers. Just random numbers.

the solution would be to write you own routine to generate unique random
numbers or query Google for posts in this group where such code has been
produced many times.

http://groups-beta.google.com/advanced_search

--
Regards,
Tom Ogilvy


"Excel Problems" <Excel wrote in message
...
I have used the Randbetween calculation in four columns, however on a few
occasions the same number is predicted in two different columns, how can I
overcome this problem