CORS error

[tvhnet2013]

Hi,

In server A, we have LightStreamer Moderator 5.1.2.
In server B, we host our web application using LightStreamer Client Version 6.1.1 build 1640.2.

Recently, our web app gets hang after running one or two days continuously on Chrome 45. We try to run it on latest Mozilla FireFox and get this error: "Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at http://myapp.serverA.com/lightstreamer/msg.js. (Reason: CORS request failed)."

Our app has run ok in nearly 2 years continuously.

Please help me to solve this problem.

Thanks & regards,

P/S: I attach our LS config file.