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Cloud SPAM filter service is unable to access LDAP port 389 on Domain Controller (Server 2012 R2).
Using a windows AD account credentials to establish connection.
My SonicWall firewall is not blocking ports 389 or 636 and I also have these ports allowed on the server's local firewall via Symantec EP.
In Group Policy, I also have "Domain controller: LDAP server signing requirements" set to None. I made this change based on a recommendation by SonicWall help.
When I try to telnet to port 389 inside or outside of domain using Putty, I get "Network error: Software caused connection abort". I have no trouble telnet-ing to port 636.
Please advise as I want Cloud SPAM service to sync LDAP users.
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Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to
It looks that you have already allowed from your SonicWall firewall. However from your Windows Server or PC try to disable or uninstall Symantec EP and Disable local Windows firewall for temporary purpose.
--If the reply is helpful, please Upvote and Accept as answer--