Serial Number got changed

If you used a non-Apple service provider to repair the laptop, then it sounds like they either replaced the whole Logic Board or they mixed up Logic Boards with another computer. If the repair shop was going to replace the Logic Board, they should have warned you about the different serial number. If the shop mixed up Logic Boards, then it doesn't inspire confidence in their procedures. Check "About this Mac" by clicking on the Apple menu. Does it show the exact same model number as before the repair? Is the CPU and memory the same as before the repair? Enter your laptop's original serial number found on the bottom case on this page and compare the information to what is shown on "About this Mac".

https://checkcoverage.apple.com/

If the repair was performed by Apple or an Apple Authorized Service Provider, then perhaps they mis-typed the serial number when replacing the Logic Board. If this is the case, then take it back so Apple or the AASP can replace the Logic Board again and enter the correct serial number this time. The Apple tool service providers use to flash the serial number can only be used on a Logic Board with no existing serial number.

dash88 wrote:

My question is:

What should i do now? Do i need to report to Apple Care that my serial number has changed?

Nothing to do. System is out of warranty and there is nothing Apple can do to change the serial number.

4. Anything else i need to be aware of?

If you have any proprietary software it may use the system serial number as part of its validation process. To the proprietary software it may look like you are using a different computer.

It is doubtful Apple or an AASP will repair this laptop with the mismatch of serial numbers, but this is probably not a problem since you didn't have Apple or an AASP repair it this time.

dash88 Said:

"Serial Number got changed: [...] Recently I had an issue with my Mac book air and i showed in apple authorised service centre and they said that there is an issue with Motherboard and you have to replace it.[...]"

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For Thought: Perhaps there is Security Software and/or Malware Installed?

When did this all start happening? Did you install some software, or connect something to your MacBook Air, prior to this Serial Number error issue?

Back up your Mac: If this were me, I would start by Creating a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the reconfigurations and/or installations. Or you could just restore it prior to all of this. Either way, backup your Mac.

Remove any Security Software your have installed on your Mac. It might be resetting this, for no more than security and privacy purposes. So, perform the removal, if applicable . Note that just removing the software from the Applications menu does not remove all of it. So, find the uninstaller, and follow all necessary procedures. Contact the software developer for direct information on uninstalling it.

Scan your Mac for Malware:

Use MalwareBytes for Mac --- This is software that searches for malware/adware. So, scan with it and then remove what is found. Once removed, uninstallMalwareBytes for Mac. Then restart the Mac.

Downloads:

1. Malwarebytes Anti-Malware for Mac
2. Malwarebytes uninstaller

dash88 Said:

"What should i do now? Do i need to report to Apple Care that my serial number has changed?"

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• Use an AASP (Apple Authorized Service Provider): For extra help, other than Apple Support Communities, see if there is an AASP (Apple Authorized Service Provider). Time is up --- the Apple Care is over with.

1. Go Here: Find Locations - Apple Authorized Service Provider.
2. Click: Service & Support
3. Enter: your location information
4. See: if there is an AASP nearby
5. Contact: one that shows up to ind out more about the services that they offer to fix this.

Also...

• Report this bug to Apple. Do you Part: I would inform Apple of this mis-hap, as it may be a bug in the Logic Board.

1. Go Here: Feedback - MacBook Air - Apple
2. Select: "bug report" for the "Feedback Type"
3. Proceed from there as necessary.

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dash88 Said:

"Anything else i need to be aware of?"

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• If you Get a New Mac: by all means, keep the Original Packaging and Receipt; that way, you can have a Box that has the same information on it as that of your Machine (i.e. serial number). Do not purchase a used Mac via a personal transaction., As one could always be scammed. So, if this were be, I would purchase a Mac from Apple, and none other.

• Try a New Association: Also, disassociate this from your Apple Account, and then re-associate it. This can be done in iTunes. Then restart the Mac. See if the Serial Number is seen as it should be. I am also thinking that a new install may reassign the correct information. So, give a new install a try, and see if it fixes this. It's worth a go. As for doing so, contact and Apple Authorized Reseller, if you uncertain about how to go about doing so.