Have and iMac, MacBook Pro and Mac mini running Big Sur 11.6.5. New seagate 8tb external drive formatted in disk utility works great. Until it's moved to another computer. MacBook Pro and mini will not mount. Cannot see the drive in disk utility on any other computer. Same issue when plugging in to iMac running high sierra or mac studio running monterey. Only works on the first iMac. An hour call with seagate and Apple turned up nothing. They are baffled. Reformatted drive on original iMac to ex fat, then apfs, then back to journaled, doesn't make a difference. I had another new 8tb seagate drive formatted on the high sierra iMac and it works on every computer. There is something wrong with Big Sur.
Chad22
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