I have 3 external HDDs - Series Raids - 25 TB each. They all worked fine in Yosemite before upgrading to El Capitan. The Drivers are not shown in the Finder Window now. Any suggestions?
Launch Disk Utility. If you see the Hard Driver on the left side, Click the "Mount" button. If the operating system already mounted the drive, an "Unmount" button displays instead. Then Click the on "First Aid" to select "Repair Disk".
He's using Raids Disks, and they were all work fine in OS X 10.10. I suppose the new raid manager and FW update will fix your problem.
I have just downloaded and installed new updates from LaCie. The trouble is gone! Thank y.