In Quickbooks version 4.0.1 I get the message:

This account cannot be deleted because there are transactions in it that have a non-zero balance.

This is if the account type (I guess) is Accounts receivable (A/R).  For a credit card, it appears to work.

This UI is awful in this case and its just one example of why I hate QB and would never ever recommend it to my most hated enemy.  You have a UI that is essentially lying to the user claiming that it will delete an account when in fact, it only marks it as inactive AND you have obscured something that needs to be plainly obvious on how to do.