Do you have a proxy setting enabled?
Try to add the exception: Tools | Options | Connections | LAN Settings | Advanced. Add subnets (e.g. 192.168.*) to the "do not use proxy..." setting or disable the proxy setting altogether (to test to see if it fixes the issue)
See if this helps identify the issue: https://help.landesk.com/docs/help/en_US/LDMS/9.6/Default.htm#Windows/security_avman_t_enable_realtime_av.htm%3FTocPath%3DSecurity%2520and%2520Compliance%7CLANDESK%2520Antivirus%7C_____10
If not look at this older doc in the About the Antivirus: General settings page section: https://help.landesk.com/Topic/Index/ENU/LDMS/9.0/Content/Windows/security_avman_h_help.htm
try to check in Agent Status Options => gather Agent Status to NEVER (under Configure = >Agent Status Options)
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