1) You can turn automatic calculation off in your workbook so every time you
want the rand function to re-calculate you have to hit the F9 key...
Tools->Options->'Calculation' Tab->Check 'Manual'
2) You can set up a UDF, something like:
Function rand2()
rand2 = Rnd
End Function
3) When you enter the randbetween() function instead of commiting it by
pressing "Enter" commit by pressing F9
instead of using
=randbetween(LOW,HIGH)
you could use
=uniqrandint(HIGH-LOW+1,FALSE)+LOW-1
entered normally (no array-formula).
See www.sulprobil.com for my UDF uniqrandint().
The second parameter (FALSE) tells my function to be non-volatile, that
means: do not recalculate with each F9.