You may face the 'The process "outgoing" blocked' message if you use the "System scheduler" sync type.
Solution
It's not a bug: actually, this message means that the sync process is still in progress now.
Our module has the special mechanism to avoid multiple sync process running. It allows avoiding the server overloading by the sync process.
So, your system scheduler runs sync every 5 minutes, for example. If you have a lot of entities in your sync queue - the sync process could takes more than 5 minutes. Until it's going other sync processes will be stopped with the notice described in your message. Once sync process is done - it'll be unblocked and your system scheduler will be able to start next sync session.
You could check your sync Queue to make sure the sync process is going.
Problem
You may face the 'The process "outgoing" blocked' message if you use the "System scheduler" sync type.