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Question: Time machine can't select drive (but the computer see it)

Hi guys, I have a 1 TB WD elements external HD with two partition, one used for archive (200gb called "HD") and the other partition used for backups (either for macbook pro and iMac, 800gb called "Backup"). The last week I replaced my MacBook Pro retina mid 2014 15" with the "new" 2015 retina 15" version (the one without Touch Bar), that is running high Sierra 10.13.1. When I try to configure time machine on this computer I can't select the "backup" partition as backup disk! What could be the problem? With the iMac (running el capitan) everything works fine, booth the partition are HFS and the strange thing is that the MacBook clearly see the two partition and it can read it! I also try to check the drive with disk utility and it's ok. Any suggestion? Thanks

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Nov 19, 2017 9:55 AM in response to Matteo Pigni In response to Matteo Pigni

It may be that it doesn't use a GUID partition scheme.

I'm not certain, but I think that is a MBR partition scheme which may be giving Time Machine trouble.

You can't convert the drive to GUID. You would have to move the files off the drive, reformat it Mac OS Extended (Journaled), then put the files back.

In Disk Utility, you will need to "Show all Devices" from the Sidebar popup menu in order to select the entire hard drive and format that.

Nov 19, 2017 9:55 AM

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Question: Time machine can't select drive (but the computer see it)