Neil:
While you indicated you are using, "SM.latest Enterprise edition," did you mean that you are running SmarterMail 14.3.5752, which is the latest version, released on 1 October, 2015?
- Have you checked the logs for the specific protocol you are running to see if there are any errors noted? If they are not set to DETAILED, you will need to change the logging level to detailed and then make several attempts to replicate the error to collect data in the logs.
I ask because APPLE made some significant changes in the integrated products which are part of the El Capitan release of OSX, making the Contacts app fully compatible with LDAP.
This information will be extremely helpful to the SmarterTools/SmarterMail development team as they attempt to help you resolve this issue.
Bruce Barnes
ChicagoNetTech Inc
brucecnt@comcast.net
Phonr: (773) 491-9019
Phone: (224) 444-0169
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