I seem to recall my microP2 card adapter working to allow me to put SD cards in my HPX370/HPX250 cameras. I recently updated to the latest firmware on both cameras and (I'm not sure if it has to do with the firmware) but every time I take my SanDisk Exterme Pro UHS-1 cards and put them in I get a "FORMAT ERR" message. When I attempt to format them I get a "Cannot Format"message. On my PX-270 these cards work fine in the microP2 card slot (interestingly enough the same error occurs with the microP2 adapter on that camera.
Any ideas? I've even tried formatting them using the P2 formatter on a computer. I was able to confirm this similar behavior with a second microP2 card adapter across all cameras.
I'm having this same issues with my HPX250. I just purchased the Adapter AJ-P2AD1G and my Lexar 2000x 300MB/s SD card. I get the same error and unable to format. I've checked and I do have the most recent firmware update = 17.46-00-0.00.