Since there is no "official" YG300 global website, you must identify your specific model version:
Go to Settings > Information in your projector menu to see the current firmware build date. yg300 projector software update upd
Plug the projector into a stable power source (do not rely on a power bank for this). Insert the USB drive into the USB port. Navigate to . Since there is no "official" YG300 global website,
Ensure the drive is FAT32 and the file is named correctly. Some units require the file to be named specifically update.upd to trigger the sensor. yg300 projector software update upd
Format the drive to . The projector will not recognize NTFS or exFAT.