I've just bought a new iMac and I've moved my two external HDs from the old Mac to the new. I've designated a 1TB HD as my Time Machine disk and started a new back-up of 92 GB (excluding all external HDs, System files, etc). The HD is mains-powered and has a USB2 connection.
The back-up ran - it took 8 hours and then stalled for over two hours at the "Cleaning Up" stage, so I just restarted the Mac and erased the HD.
I've repeated the process and the message of time to go varies from 6 to 7 hours.
This never happened on the old Mac - a new back-up took only an hour or two.
Is something wrong?
michael

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