To resolve this issue, select everything that is in the postal code box and delete it. Then re-type the postal code, making sure to use only numbers & letters and no special characters or spaces. There should be a total of 6 characters ie: a1b 2c3 (letter, number, letter then a number, letter, number).
If your postal code is from another country, at the top of the TurboTax Online page, please answer YES to the question: “Is your mailing address outside Canada?”. You’ll now be able to choose your country and enter your foreign postal code.