Mac Logic Board Replacement WILL Lead to Issues with Time Machine and iTunes   - 1,550 Views,

The biggest issue we see is that Apple knows about this, and doesn’t warn the customer before swapping out the logic board. A simple warning from Apple before replacing a logic board could save Apple customers hours - days even - of stress, heartache, and futile searching and effort; but Apple doesn’t give their customers that warning. So, we are giving you that warning - here’s our word to the wise.

Here’s the deal: every computer is assigned a MAC address. Despite the coincidental name, in this case MAC stands for “Media Access Control”, and MAC addresses aren’t unique to Mac computers - all devices that use network connections have them. It’s a unique identification number assigned to your computer so that other devices and programs with which it may connect can recognize it as definitely being that computer. Think of it as a Social Security number (SSN) for your computer.

In the case of a Mac computer, programs such as Time Machine and iTunes use your MAC address to authenticate and ensure that the computer connecting to Time Machine or iTunes is in fact a computer that is authorized to make that connection. After all, you wouldn’t want your neighbor to be able to connect to your Time Machine backup and to access all of your data, or their teenage son to be able to connect to your iTunes library without your permission.

So, if the computer attempting to connect to Time Machine or iTunes doesn’t have an authorized MAC address, the connection will fail.

On Mac computers, MAC addresses are created and assigned by the logic board. This means that if you have your logic board replaced, Time Machine and iTunes will no longer recognize your computer as an authorized computer.

Worse, there is almost no way to ‘fix’ that, which means that you have to re-permit your computer for iTunes and, far worse, access to your previous and current Time Machine backups will be lost, and you will have to perform a brand new Time Machine backup.

We say “almost no way” because there is a method to force Time Machine to let your Mac with the new logic board access the old Time Machine backups, but it is complicated, somewhat risky, and doesn’t always work. (In fact, in our case Apple themselves spent two days trying to make it work before they had to admit defeat.)

The irony in this is that Apple always tells you to be sure to make a backup before bringing your computer in for repairs (and rightly so), but what they don’t tell you is that that backup will be useless if they put a new logic board in your computer.

With respect to iTunes, which also uses your MAC address, iTunes only allows you to authorize up to 5 computers per instance of iTunes and access to the iTunes store. Moreover, the only way to deauthorize a computer (which is actually deauthorizing the MAC address) is if you have already maxed out iTunes at 5 computers, and then you have to deauthorize all 5, and start all over. (You won’t lose your iTunes library or anything like that, but you will have to reauthorize all of the legitimate computers). Plus, you can only use the ‘deauthorize all’ option once a year!

So, what’s the lesson here?

First, if your Mac is going in for repair, give them clear instructions that they are to call you and get your authorization before replacing the logic board. (Apple will replace a logic board on the fly without telling you; on their end, they may well be giving you a $1000 repair at no charge, and see it as largesse, and indeed we were grateful to have that repair done, but we should have been told first (a fact with which the store manager agreed, and offered to suggest that protocol change to corporate)).

Second, if you think there is a chance that you are looking at a logic board replacement (and how could you tell? Our Mac was going in for a battery issue!), deauthorize your computer from iTunes before you bring it in. It is very easy to deauthorize a single computer from iTunes if you are using that computer to connect to iTunes; it’s only when you can’t access iTunes from the authorized MAC address, to deauthorize it, that you have to use the “deauthorize all” option to kill it.

Third, if you think there is a chance that you are looking at a logic board replacement, don’t just back up your computer, but be sure that you have everything that you don’t want to lose from your current Time Machine backup also resident on your computer. This is counter-intuitive, because you are thinking “what if they wipe my hard drive?” But, if your hard drive gets wiped, you can restore from your existing Time Machine backup. On the other hand, if your hard drive comes home to you with everything still intact, you are going to have to make that new backup to Time Machine, because the old one won’t pick up where it left off, so you want to be sure that you have everything you want on your computer before you start all over again with Time Machine.

Finally, if you tell Apple to call you before doing a logic board replacement, and you do get that call, and you haven’t already deauthorized the computer from iTunes, and you haven’t already made sure there is nothing in your existing Time Machine backups that you can’t afford to lose, then thank Apple very much for calling, and go pick up your Mac from Apple and use it to deauthorize iTunes, and to get anything you want from Time Machine back onto your Mac, before they replace the logic board.

There, if this warning saves even one person the stress, the frustration, and the days lost, it will have been worth it.