Tech Tool Pro is telling me the hard drive on iMac 27' late 2013 model with 10.14.6 is failing.
I made a copy of HD with Super Duper on an external hard drive and want to know how to make it the start up drive until I can get a new computer?
iMac 27″, macOS 10.14
Welcome to the Apple Support Communities.
First, it is highly recommended, if possible, that you use an external SSD. The external HD will be very slow.
Secondly, what make and model is this external HD?
Jack
Look in System Preferences - Startup Drive, then select the drive you want and retart. It is that simple!!
It is a Seagate One Touch 2TB External Hard Drive HDD.
Thank you for the reply.
how to use external hard drive and a start up disk
