Only TUFLOW DOS Window
This happens if the run option you have specified in Notepad++ is not complete. Check if "$(FULL_CURRENT_PATH)" syntax has been provided along with the link to the TUFLOW exe? Delete the existing shortcut and recreate it with the complete syntax.
Eg. "C:\TUFLOW\Releases\2018-03\w64\TUFLOW_iSP_w64.exe" "$(FULL_CURRENT_PATH)"
"$(FULL_CURRENT_PATH)" tells notepad to pass the currently open file to TUFLOW exe as the input file.