When a MACE MM QR or NVITE Reader is installed outdoors you could have issues reading QR codes when it is very bright outside. When for example the sun shines directly on the reader or on the QR code, the reader is not able to read the code.
We see this issue when the Illuminator of the NVITE reader is turned off. When this is turned off, the camera in the reader is not able to compensate the brightness settings.
Turn on the Illuminator in the NVITE Config Tool, you can find this option under the menu QR-CODE.