I have Mango running on a Linux box core 2.4.0 and modbus 1.4.8 talking to several devices using serial over xbee. All works fine for over a year. I decided to install the latest mango in OS X El Capitan release. The system works for a while then I get the "point may not unreliable message" for modbus points. The http retriever points refresh ok.. The only way I can make it work is shutdown mango and remove and connect my USB serial connection. It runs for 2 hours or 15 minutes then cannot collect data. I have core 2.7 and modes 1.6.5 installed in osx. I installed via download and then did an in-1place upgrade in Mango UI.
If go back to the linux box and plug in the USB serial, all is good. I'm at a loss. I first I thought it was some energy saving mode and disabled that.