Recurrent Ethercat error while running program

I am started getting following errors while running my Program. The program uses KUKA RSI. My controller is KRC4. The program runs fine for few days and then following errors halt the robot's execution. Can anyone help?
Error List:-
KSS26078 Ackn. Position invalid
KSS01034 Error on Writing, E CAT – Ctrl Bus
KSS01033 Error on Writing, E CAT – Ctrl Bus
KSS26066 Connection to Motor Driver re-Established
KSS13008 Ethercat Bus error
KSS15073 error in Safety Node of Drive
KSS15002 Communication Error Safe Device
KSS26063 Ackn. Ethercat Connection Lost
Kss15003 Communication Error Safe Device
Kss26066 connection to motor driver restablished
Kss15016 Stop due to Stand Still Monitoring Violation
Kss02858 Stop due to field bus error
Kss26147 Communication Error KPP(1)
Kss26014 General Power Supply Error

I have tried following things but it didn't solve my problem permanently:-

1. Switch off the controller, removed all LAN connections inside controller(green coloured cables inside controller) & put it back again, then turn ON.

2. Login to user group Expert, click on Shutdown then cold start+Reload files, click on Reboot PC.