[HELP] sloeber does not want to program Ardrino!

problem... i keep getting

Starting upload using arduino loader Starting reset using DTR toggle process Toggling DTR Continuing to use /dev/cu.usbmodem1421 Ending reset

Launching /Applications/sloeber.app/Contents/Eclipse/arduinoPlugin/tools/arduino/avrdude/6.3.0-arduino6/bin/avrdude -C/Applications/sloeber.app/Contents/Eclipse/arduinoPlugin/tools/arduino/avrdude/6.3.0-arduino6/etc/avrdude.conf -patmega328p -carduino -P/dev/cu.usbmodem1421 -b57600 -D -Uflash:w:/Users/allenpan/Library/Mobile Documents/com~apple~CloudDocs/Self-Driving/WorkSpace/Ethernet_UDP/Release/Ethernet_UDP.hex:i Output: avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x30 avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x20 avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x30 avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x20 avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x0d avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x0a avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x0a avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x5b avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x49 avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x50

avrdude done. Thank you.

avrdude finished upload done

and nothing been uploaded/updated

Can you program the Arduino using the IDE?