Plug the USB drive into the projector. Hold the power button (or follow your specific model’s button combo) and plug the power back in.
from your settings menu? If you provide it, I can help you narrow down exactly which update file you need for your specific hardware revision. yg300 firmware link
The YG300 comes in two main variants: the (AV/USB/HDMI) and the Pro/Sync (which includes Wi-Fi/Mirroring). Links for the Standard model will not work on the Sync model. Always verify your model number before clicking "Update." Plug the USB drive into the projector
If your box says Lumos, Meer, or Apeman , go directly to their specific support sites. They host custom firmware versions tailored to their specific builds. yg300 firmware link
Turn off the projector and unplug the power cable.