Have you seen SAS Usage Note 43919: Authentication on AIX 6.1 fails ? Could this apply to your situation? Can you say which version of SAS you're using, how you have your SAS authentication configured (PW, PAM, LDAP, etc), and how you have your AIX authentication configured? Can you post a sanitised version of your !SASROOT/utilities/bin/sasauth.conf file? If you follow the usage note link to the Config Guide and look in (for SAS 9.2) Chapter 3 "Post-Installation Configuration for User Authentication and Identification" you will also see how to create a sasauth debug log to help with troubleshooting. Perhaps you could post back any error messages or other clues. The SAS 9.3 version of the config guide for UNIX documents a few AIX specific options too (such as AIX_USE_AUTHENTICATE which looks interesting). In the documentation for the LDAP method it states that "sasauth supports crypt, SHA, and SSHA forms." - I'm not sure if this is the same list for the PW method on AIX but if you contact SAS technical support they should be able to clarify.