The Australia Post 4-state customer barcode carries an address's DPID - the 8-digit Delivery Point Identifier Australia Post gives every address - so sorting machines can route the letter. Each bar is one of four kinds: full height, top half, bottom half or short.

Standard Customer

Customer Barcode 2, with customer information

What it holds
Characters	The 2-digit FCC (Format Control Code), the 8-digit DPID and, in some barcodes, customer information - all typed together, with no spaces.
Check digit	Error correction (Reed-Solomon) is built into the bars by Labeljoy.
Readable text	The FCC, the DPID and any customer information, with a space between them.

Modes
Standard Customer	For ordinary mail. Start with the FCC: 11 - the Standard Customer Barcode: FCC and DPID, 10 digits. 59 - Customer Barcode 2: then up to 8 digits of your own, or up to 5 characters (letters, digits, space, #). 62 - Customer Barcode 3: then up to 15 digits, or up to 10 characters.
Reply Paid	Reply paid mail, FCC 45.
Routing	FCC 87.
Redirect	Redirected mail, FCC 92. A new Australia Post barcode starts in this mode: choose Standard Customer for ordinary mail.

For Reply Paid, Routing and Redirect you can type the DPID alone, 8 digits: Labeljoy adds the FCC the mode stands for. Typing the FCC as well works too.

The rest of the settings - text position, quiet zone, color - are in the Barcode section.

What goes wrong
FCC and DPID must be numeric data.	The first 10 characters must all be digits - no spaces between the FCC and the DPID.
Invalid Format Control Code.	The FCC isn't one the mode takes: 11, 59 or 62 for Standard Customer, 45 for Reply Paid, 87 for Routing, 92 for Redirect.
Input data wrong length.	Fewer than 10 digits for the FCC and DPID.
Input is wrong length for Format Control Code 11.	FCC 11 takes no customer information: exactly 10 digits.
Input is wrong length for selected AusPost symbol.	Reply Paid, Routing and Redirect take the DPID, 8 digits, or the FCC and DPID, 10.
Customer information this long must be digits only.	Over 5 characters (FCC 59) or 10 (FCC 62), the customer information can only be digits.
Invalid data for Character encoding.	The customer information has a character it can't hold - only letters, digits, space and #.
Input is wrong length for Customer Information Field.	More than 8 digits (FCC 59) or 15 (FCC 62).