You may need to open port 17871 if you use a third-party firewall. Windows firewall doesn't interfere with calls to the iManage Work Agent, because the Agent listens on the loopback only (127.0.0.1). But other third party firewalls may interfere and therefore need to be configured to allow inbound calls to my.imanlocal.com:17871 or 127.0.0.1:17871.
If iManage Work Desktop for Windows is installed in multi-user environments such as Citrix, iManage Work Agent Service listens on 17871 and individual Work Agent instances running under each signed in user's account listen on the range of ports immediately above 17871 (17871 to … ).