Example error message: 

"Bpost international is currently unavailable"

Cause:

This is usually due to a configuration error, regarding pricing for the specified delivery method.

Namely, if you choose to work with the table rate, you need to configure the values for these

Solution:

Configure the prices for the table rate

How to do this:

1) In your Magento Admin Panel, go to System > Configuration

2) Then got to Sales > Shipping Methods

3) Choose bpost Home delivery international > Rates > Export table rates file > Export CSV

4) Fill in the required fields in the CSV file, and upload it in your module, 

Note: Should you not see the button, then go to the top left of your screen, to "Current Configuration Scope", and in the dropdown menu select your webshop instead of the Default Config

Then proceed as explained in point 3 and 4

Do not forget to Save your configuration!! (button top right of the screen)