In the Terminal window, type df –h and hit Return. The recent Western Digital "easy store" and "My Book" hard drives have a Mac Sierra 10.Format External Hard Drive to Supported Format. You’ll have to reformat your USB to a file system Mac does recognize. One way out is to reformat external hard drive Mac and Windows would be able to recognize - such as the exFAT format.Find and click on your external hard drive icon. Alternatively, this can happen due to: Non-functional USB. The new M1 iMac is a sleek, stylish and surprisingly affordable photo and video editing machine.Click on the Mount option from the menu bar at the top.
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If this does not work, you can connect one monitor to the dock and plug a USB-C.
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I don't know what happened that the Raid controller is not recognizing drives. And my apple usb wired keyboard doesnt work either. And the Mac mini up to 1 6K at 60Hz over USB-C/Thunerbolt and 1 display. Here 4 ways are covered to fix an undetected external hard drive. The most common issue is that the Mac is not recognizing the USB device or it doesn’t recognize the OS X software required to use it. It seems IO controllers on the M1 don't work very reliably. Internal errors – file system error, outdated drivers, unknown errors, etc. If you completed a previous backup successfully, verify that backup: Press and hold the Option key while choosing Verify Backups from the Time Machine menu in the menu bar.