I recently had a hard drive failure (which I now blame on the SATA cable because my SSD became corrupted). I have the stock hard drive that originally came with my MacBook Pro, and I have put it in an enclosure so I can use it via USB. When I restored my hard drive using Time Machine, the computer kept going to sleep despite being connected to power. After about 12 hours being stuck at the same spot, I decided to force shut down the computer and then restart the transfer. When the computer booted back up, all (or at least most, and some data I haven't needed lately) was there. I tried to open the Messages app and it would not open. I reinstalled the OS using the option that would allow me to keep my data, which fixed some errors that the system had been giving me. After researching online, I learned that I should remove the file that stores Messages information (I forget what it was called). My Messages now open, but all previous ones were deleted.

When I get the SATA cable fixed, I want to restore from the Time Machine backup because I still don't fully trust the OS on the hard drive I'm using right now. However, I have other files and messages that have been created that I want to transfer. How should I migrate these files without overwriting any data?

1 Answer 1


When migrating my system I often "abuse" the Migration Assistant to import my files to a dummy user. Then I create a second user and copy only the files I really want to the new user. Once I am done I delete the dummy user. This strategy should also help you to get your files together.

Some other hints that could interest you:

  • You can use rsync with the -c command in Terminal to compare files by their checksum. This is a very slow process because every file will be fully read. However, this gives you absolute certainty if two files are identical or not. Using e.g. rsync -anrcv /Volumes/BackupDisk/OSX/Users/me/ /Volumes/OSX/Users/me would print all files that have different checksums, i.e. are potentially corrupted. I sometimes use that when I suspect that a drive has corrupted data.
  • You can use caffeinate in Terminal to keep your Mac from sleeping.
  • Thanks. Do you know if the caffeinate will work even when Migration Assistant requires that all other apps are quit before the process?
    – Rajiv
    Feb 11, 2017 at 20:00
  • Probably not. It is strange your Mac went to standby...
    – n1000
    Feb 11, 2017 at 20:06
  • I'll have to file a bug report, because this was on a public beta
    – Rajiv
    Feb 11, 2017 at 20:08

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