Swap Hard Drive 2010 MBP to 2011 MBP

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Level 1

4 points

Swap Hard Drive 2010 MBP to 2011 MBP

Hi Fellas.

The point of this exercise is to allow the full use of a certain admin user account from a 2010 17" MBP running MacOSX 10.13.6 onto a 2011 15" MBP running MacOSX 10.13.6.

Usually when I upgrade or cross-grade a Mac, I simply swap the Hard Drive from one to the other. Okay? Been doing this since 1998. When I need to upgrade or change out a HDD, I clone using CarbonCopyCloner or equivalent.

When I swapped the HDD from the 2010 to the 2011 MBP things didn't work as expected. (The 2010 MBP has a bad display.)

Mail.app was a real pill. Mail would not allow me to access any email accounts to receive or send, I have several. It said the passwords were incorrect. Even changing passwords on my server and inputting the new passwords into Mail did nothing to correct the issue. I think it made no attempt to connect to the servers.

Firefox launched but said it needed to create a new "Profile". When I gave it leave, it couldn't read/write to the "Profile". I checked the folder and files found them with normal permissions.

Brave Browser launched and was normal except it deleted all the extensions I had installed and deleted the extension files in it's Application Support folder.

After many internet searches for solutions and no answers, I ran out of things to try and ran out of time. I returned the HDD to the old 2010 MBP and everything worked as it always has. I thought maybe Apple in their un-wisdom had designed High Sierra to disallow HDD swapping. (BTW When I boot up the 2011 from the 2010 via Target Disk Mode everything works as expected!)

The 2011 MBP had been in storage for a few years and still had Mac OSX 10.8.x. So then I installed MacOSX 10.13.6 over 10.8.x on the 2011 and then using Migration Assistant I copied over my main admin User Account from the 2010 MBP.

The result was precisely same result as swapping the HDD, as per above.

Any body run across a situation like this before? Anyone got a suggestion or two? What am I missing here?

Thanks for reading my post.

Earlier Mac models

Posted on Jan 11, 2026 5:24 PM

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Answer 1

John Galt

Level 10

155,714 points

Jan 12, 2026 2:36 PM in response to SamSimple

SamSimple wrote:

... I thought maybe Apple in their un-wisdom had designed High Sierra to disallow HDD swapping.

No, nothing like that is going on. You will however run into the problems you described due to the fact passwords and other security-related factors are linked to device UUIDs (universally unique device identifiers).

It will work just as it worked for you in the past, but it will be inconvenient.

High Sierra will have its own problems with many email service providers and websites but that's not related to swapping the HDDs.

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Answer 2

Jan 11, 2026 5:34 PM in response to SamSimple

High Sierra is old enough that some e-mail providers might consider its Mail app to be insecure, and either disallow connections, or require the use of special procedures.

For instance, if you were connecting the High Sierra Mail app to a Google Mail (Gmail) account, you might now need to follow Google's instructions for creating and using an "app password" (a password used ONLY with Mail).

This wouldn't be related to swapping hard disks, per se.

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Answer 3

SamSimple Author

Level 1

4 points

Jan 12, 2026 5:49 PM in response to Servant of Cats

Thank you for you feedback. Appreciate it.

I understand about the UUID. I thought of that but the problems are not consistent with a UUID problem.

For example, that doesn't explain to me the normal operation via Target Disk Mode or otherwise external HDD. The UUID would still be different than the 2010 MBP.

In 2023 I went on an extended business trip of two months and took my 11.6" 2015 MacBookAir and left the 17" MBP home. Before I left I removed the HDD from the 2010 MBP and placed it into an external USB enclosure. I used it every day while I was on my trip, everything worked as expected.

The email addresses are not part of the unWonderful World of Google, nor of Yahoo nor M$ nor any other "big-box" email provider. I don't use google in any form where it can be avoided.

Please explain to me why migrating my user account using Apple's Migration Assistant does not overcome the UUID problem (if there is one) for email that could occur with a HDD swap? Shouldn't Apple's programmers and testers encounter such an event before releasing to the public?

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