RuntimeError: Default process group has not been initialized, please make sure to call init_process_group (train_caption.py)

[Y-HuiMing-Y]

Thank you for taking the time to look at my problem！
When I was training train_caption.py on windows, I set nproc_per_node=1 and default=False in main function, but I still got

"RuntimeError: Default process group has not been initialized, please make sure to call init_process_group "

Is there any need to set?
Thank you very much for your help!