I conclude the originally installed SSD is no longer usable. I removed it and successfully booted the machine from a USB installer flashdrive. I then installed a 340GB HDD that I had salvaged from an old laptop and successfully booted and installed TrueNAS SCALE. However, the replacement drive is showing signs of problems and likely needs to be replaced. I don’t need a large storage device but would like an inexpensive one. What do you suggest? The working storage will be on a Western Digital 20T USB drive.