Is your buffer being detected?
If not, you first need to resolve this issue.
If your buffer is detected? Then set log raw data to permanent and see if it logs any data to raw.txt. If no data logged, then stop TNG service and connect to the buffer with hyperterminal/putty or PABX3 to see if you can communicate with the buffer.
For more details refer to forum post: My TNG buffer is not being detected
If you are at the client you are welcome to give the call centre a call to assist you.