KepServerEX 7.0.236.0 Siemens S6 Ethernet IP S7-1200 Tag Unable to read data from Device

I configured Kepserver V7 to get data from Siemens S7-1200 using TCP/IP ethernet. I followed all the steps shown on this guide. https://support.ptc.com/help/kepware/drivers/en/#page/kepware/drivers/SIEMENSTCPIPETHERNET/HelpContents.html#

However, I kept having error saying “Data block - ‘DB131’, block start = 0, block size =32, Reason = ‘Device returned protocol error’. Error class = 0x81, Error Code = 0x4.” I researched this error and I learned I needed to install TIA Portal Exporter installed to change .ap file to .tpe file. Then import the .tpe file to kepserver device. This resulted error saying “Error initializing the Openness API. Please verify all necessary components are installed”. I reinstalled TIA portal to verify openness is installed and it was installed. 
Please advise how I can resolve these issues.