This function allows you to block sales to a Customer Account when they owe money on it.
The customer can still pay for the items with another tender, however they cannot have any sales charged to their account.
Go to Setup > Global Options > Customers > User-Defined Yes/No Fields > Change one to: Account on Hold.
Go to File > Customers > Customers > Modify > Account On Hold.
When the customer is added to the sale a message will display on screen.
If you attempt to charge the sale to account, the message will display again and prevent you from charging to account.
Any other tender can be used.