How many characters are required in the username and password? Both the username and password must have at least 8 characters. There is no upper limit. The password is case sensitive. Related ArticlesI have received an email saying that my account is due to expire. What should I do? August 25, 2015 I have forgotten my ACS username/password. What should I do? August 25, 2015 I have completed the ACS renewal process, but now my account is not activated. What should I do? August 25, 2015 I tried to login with my ACS details but it says my account is not activated. What should I do? August 25, 2015 Will I be reminded before my registration expires? August 25, 2015