Sending Document Out for Signing: Authentication Failed Message after Clicking Specify Where to Sign

[defaultc2r3sq7ekvh3]

We recently acquired two Acrobat Pro DC lincenses for users who need to send documents out for signing.  As the Team administrator, after doing the installation on each user's workstation, we did some testing.  After selecting the Send a Document out for Signing option, a form pops up as shown in the attached docuement.  After selecting the document to send for signing and selecting the email address of the users who need to sign the document, the next step is to click the "Specify Where to Sign" button.  Upon clicking this button an error message "Authentication Failed" appears in the lower left corner of the form.  The user is not allowed to proceed any further.

QUESTION:  What is the meaning of this "Authentication Failed" message?  And, what is the remedy for resolving this issue?  

Thank You,

Dale

[Tom38939428ib3n]

Hi Joseph,

Did you find that this change needed to be done on your Marshal service (or equivalant software that monitors and filters traffic via proxy servers) in the form of a rule, or was it on your firewall that sits behind and takes receipt of traffic from the proxy servers?

Kind Regards,

Tom