MeToo, i had and have the same issue with my Kerio Firewall. There is something called RPC that is used to let these program parts, front(BOINmgr)/middle(BOINC)/end(e.g. wcg_hdc_tma...) to talk to each other. Had to activate the code-injection permission and ABB (application behavior blocking) in my Kerio Firewall. The Support from Sunbelt gave me some settings, as its not allowed for security reasons to manually add the latter....it has to detect it and than permit it permanently by saying yes to an auto-rule.

Unfortunately, the issue has not gone entirely away....occasionally, every other day the BOINC front hangs up. Simple disable/enable of the firewall re-establishes the connection. Whilst the front is stuck, no notices, no logs, the science just continues.....its only a problem by the time the science finishes and the BOINCMgr has to do its transmission part. If blocked by the Firewall, nothing happens until i do my thing. Till then still looking for the permanent solution....setting the network to suspended in BOINC has at least never invoked the blocking stat.....pure speculation, but there's someting to this 3 way comms....from science to BOINCmgr to the internet.

Anyone an answer as more than a few seem to suffer from this?!?