background
This is a nostalgic/remember blog post. In 2018 (the end of 2017?), I purchased a Hitachi 1T bare disk, and then purchased a hard disk box, ready to be a backup disk for Mac Time Machine.
The problem
The Mac automatically prompts that it cannot "write operation" when it is powered on for the first time
solve
Remind you that the bare disk of HGST Hitachi (acquired by Western Digital), the Mac will automatically prompt that it cannot "write operation" when it is powered on for the first time. Click Initialize in the prompt box, and then erase, the parameters are directly set by default, and then partition and format as FAT after completion. I divided 500GB of 1TB mechanical hard drive into Time Machine and formatted the remaining 500 into FAT for data storage.