Numbers in a range

[PpkMan]

Within a record I need to ensure that the numerical value of a particular field falls in a range that is specific for that record. The range is quite different for each record. How do I define that field?

Example- I am entering lists of certificates issued by my clients. The unique reference number on each certifcate must fall within a specific range, say 201 to 250, for that client. Certifcates issued by another client will be in a separate and different range, say 401 to 450.

I have created a field for entering the first number and a separate field for the second but how do I define the field in which the actual certificate number will be entered. If I validate by putting field names in the range boxes it does not work!

Help please>

[RalphL]

Validate by calculation Number >= Min value AND Number <= Max value