This issue can be resolved by adding a System Parameter Maintenance entry within Proclaim by following the steps below:
Enter the System Parameter Maintenance Program.
Click on New.
Within the Key field type Display PDF in Adobe .
Leave the Code field blank.
Within the Value field type Yes.
Click on Save.
Exit the program.
If you or your system administrator does not have access to System Parameter Maintenance, please raise a support ticket and quote this article.