Receiving error code 0xffff8104 or 0x00008104 when attempting to read or write from/to a Siemens S7-1200 or S7-1500 with firmware revision 4.0 or higher. Same code works fine with S7-1200 or S7-1500 firmware revision 3.x or lower.
Firmware revision 4.0 or higher offers added protection settings that can be used to prevent external access to controller registers.
The enhanced settings can be found in Step 7 CPU Properties, General Tab, Protection settings:
Follow these steps in Step7 (TIA Portal):
- Open the PLC project in the S7 TIA Portal software.
- Go to Project View
- In the Project Tree window, select the device that is causing the error.
- Hit Alt-Enter to bring up the Properties dialog.
- On the General tab, select Protection.
- Ensure that one of the following options is checked
- Full access (no protection)
- Read access
- HMI access
Note: At this time, the ASComm.NET Siemens S7 Ethernet Driver does not support the use of a password.
- Check 'Permit access with Put/Get communication from remote partner.'
- Click the OK button to save the settings.
- Compile and save project, then download modified program to controller.