The purpose of the Sending Tab is to tell Top Dog how you would like outgoing email to be handled

Prompt for confirmation if background application tries to send mail.

This is a virus protection feature.
Normally, when you send a message your email program is the currently active program.
Viruses usually send from the background, either by accessing the internet themselves or by telling your email program to send mail via a script.
The virus then sends out copies of it's self to everyone in your address book.
In either case the virus does not want you to be aware of what it is doing and so sends mail out from the background.
This is in contrast to what happens when you normally send mail.

Normally when you send mail, you press the send button on your message and the message gets sent immediately. In other words your email program is in the foreground when you send.

The major exception to this is if your email program allows you to schedule messages.
In this case your email program may not be in the foreground when it sends a message.

To disable this option simply uncheck the box, or when you are prompted press "Ignore".
Pressing "Yes to All" at the prompt will enable background sends when the current program is in the foreground.

You can edit the list of known email programs from the button on the security tab.

Process outgoing email.

If this option is checked then Top Dog will process outgoing email.
Processing outgoing email allows Top Dog to do many useful things such as:

• Whitelist replies to email you send out.
• Remove any information added by Top Dog when replying to email.
• Training Top Dog's Neural Network to recognize email that you are interested in receiving using.

Remove Top Dog Information from message when sending.

If this option is enabled, Top Dog removes any information from the outgoing message that may have added.
This only applies to messages you are replying to.
In this case, Top Dog may have inserted information into the email on it's way in, which it will now remove on it's way out again.
You may want to disable this option for a specific email if you routinely want to send this information on to others.
In general you will probably want to leave this option on.

Whitelist any email that references an email you have sent.

If this option is set then Top Dog will whitelist the Message id of any email you send.
(The Message id uniquely identifies the email).
As a result any email that references or is a reply to an email you send gets whitelisted.
This is a good way to ensure that replies to email you send out do not get mistaken for spam no matter how spammy they may look.
It is a good idea to leave this option on.

Enable extended mail sending options.

If this option is checked then Top Dog will hold outbound email for a few seconds before sending it out.
The purpose of this is to allow you the opportunity to specify additional options as to how you would like the outbound email handled.
Details of these options are documented on the Status Tab

Hold mail for X seconds before sending.

When messages are sent, you can ask Top Dog to hold the message briefly before sending it.
These messages show up as "Messages Being Held" on the Status Tab.

The purpose of this delay is to allow you time to tell Top Dog if you would like the message handled in any special way before sending it by pressing the "Send Mail Options..." button (also on the Status Tab).