S7 driver communication error code

[Tushar10ap]

I am trying to communicate with S7-1500 PLC with S7 driver.
My setup includes, S7-1517H-3PN (redundant) PLC and Redundant SCADA.
PUT/GET communication setting and optimized block access settings are done in both the PLCs.


PLC-A is communicating with SCADA without any problem.
but PLC-B is frequently disconnecting and showing below error code in log viewer -

SEVERE, 13/s7, Common AGLink error (0xfff50005) for PLC_A9101(3/1), 3, 33028

in Info panel, last error code is "00020: Error in alive check for device $1, plc$2:" (see the attachment).

Help file says that positive error code caused by internal s7 driver fault.
Could anyone help me in this issue, am I missing any config?

[kilianvp]

0xfff50005 means Invalid context

[Tushar10ap]

Thanks.
This problem is resolved. there was differences in the PLC program in both PLC (may be PLCs were not synchronized).
After resetting and downloading program again in PLCs, this problem get resolved.