Users logging on to CICS running ACF2/CICS are getting error message DFHCE3500

Document ID : KB000123046
Last Modified Date : 02/01/2019
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All users cannot logon to any of our CICS regions  The signon fails with error message. 'DFHCE3500 Unable to interpret keyword data. Sign-on is terminated.'  How is this fixed?
Apply PTF RO97057, and make sure your ACF2/CICS parms have this in place:
Additional Information:
PTF RO93181 causes all CICS regions to unconditionally consider          
password phrases supported. This was done in order to support            
Advanced Authentication Mainframe (AAM) where more than eight            
characters need to be supplied in place of a normal password.            
This has the effect of causing the distributed CICS Signon               
Program, ACFAEUSC, to use the expanded signon panel. If a local          
installation has customized ACFAEUSC and does not need or wish           
to use the expanded signon panel, this effect could cause the            
practical loss of their customization.                                   
This change will evaluate the current ACF2 MVS Password Phrase           
setting and state of CA AAM and IBM MFA during CICS Initialization       
and consider password phrase support active only when called for.