When trying to login to the Workfront Proof Mobile App it returns:
"Your Username or password is incorrect. Please try again."
When using both Workfront & Workfront Proof you will need to install both the Workfront Mobile App and the Workfront Proof Mobile App.
First, Login to the Workfront Mobile App and navigate to the desired document you would like to Proof > click the three dot ellipsis in the upper right and choose Proofing. This will automatically launch the Workfront Proof Mobile App and log you in. Now you can work with proofing in the document.
If you try to launch the Workfront Proof Mobile App by itself it will attempt to login to a stand-alone Workfront Proof system, not the one integrated with Workfront. This is why the error is returned.