Tomorrow (2016-3-25) we will be rolling out odrive single sign-on for the forum. This means that you will no longer need to sign-up or login with a separate user and your forum account and odrive account will be linked via e-mail address.
When this kicks in, you may be required to validate your odrive e-mail (for security purposes). A code will be e-mailed to you which you will put in to the validation page. After that you are good to go!
If there is a possibility that your e-mail differs between what is in odrive as your contact e-mail ( https://www.odrive.com/account/profile ) and what is in your forum profile, please make sure you change one or the other to match so a new forum account is not created.