Are your users not getting their proof notifications? If so, vote this topic up! Spoofing is likely why the emails are not getting through to your reviewers and approvers.
Currently Workfront allows for disabling of spoofing for Workfront notifications, however this option is not currently available on the ProofHQ side. It is logical not only that the entire system should have the same capabilities, but also that a setting, which is considered by most ISPs as spam behavior, should have an ability to be turned off. Gmail currently automatically blocks spoofed emails and sometimes this block cannot be turned off.
To have proofs appear that they came from the proof creator's email address is a nice benefit to some, however if this setting is a requirement that is causing emails to end up in spam folders, IT admin email quarantines, or lost in cyberspace, it is a serious workflow problem. Project management systems are meant to make workflow more efficient. If you upload a proof and then ALSO need to send outside emails at every stage of the proofing process to all who are involved, it becomes a nightmare for project managers.
Please correct this oversight so all reviewers and approvers can receive automatically generated emails when proof action is needed, just like how the system was designed.