Payment Over-Applied is a feature request to block users from entering Applied amounts that exceed the payment amount.
If you have a positive payment with a negative unapplied amount--or a negative payment with a positive unapplied amount--the payment cannot be saved.
Prepayments or payments that are fully unapplied or partially unapplied are perfectly okay, and there are numerous options in Big
Big Business now blocks over-applying a payment to prevent problems reconciling.
If you need the option to Over Apply, in order to save the payment temporarily, you can now enable it on the Advanced II tab of the Company Card.
Single User is the Big Business app for one user. Only. It is variously called Standalone, Demo, 1-User, and Single-User and only needed when you work alone.
To connect multiple users, Big Business uses Client/Server architecture, where a Server app is installed on a central computer, and the Client app is installed on each workstation that needs to connect.