@Kate651
Kate there are many countries that do not support or use Iban codes, both Canada and Australia being two!
The common way around this is to include 4 zeros before the account number.
This link may help you convert your account number to an Iban code, but there is no guarantee it will solve your problem......
http://www.creativeeyes.at/tools/iban.php
Best to speak to your bank and be guided by them.....although lots of bank staff in Australia will look at you blankly and say...."an Iban, what!"
Good luck!
Cheers.....Rob