Posting this to point out a few things to anyone else coming to this thread to help inform people and provide a bit of explanation for some of these issues.
Sam-_-_-_ wrote:
My friend has an early 2015 13 inch MacBook that he gave me to fix. The original issue was that the trackpad and keyboard were unresponsive.
FYI, when both the internal Keyboard & Trackpad fail at the same time, this was probably due to a bad Trackpad IPD Flex Cable which on the 2015 model has a high rate of failure.
I attempted to update the OS to Monterey 12.6 but something has gone rather wrong with file vault somehow.
FYI, upgrading the OS is never the answer unless a particular app is known not to work with the older OS. Doing so compounds the problem because now you must still deal with the original problem and any new problems due to compatibility issues with a new OS. Installing an update patch to the existing OS is Ok as it may be fixing a known issue.
It now won't boot up if plugged in to power. It will boot up on battery and says file vault decryption is very nearly finished but it can't finish unless plugged in. If I plug it in when it has already booted on battery, it will restart and not be able to boot.
Sounds like some sort of hardware issue that will need to be repaired.
Now of course I should have backed up before updating but I did not. The obvious solution would be to do a fresh install then restore but I cannot do a time machine backup on battery while FileVault is decrypting.
It is extremely rare that Filevault is the source of problems. Encrypting/decrypting is a major change for the older 2017 and earlier Macs since every part of the storage device will have its data rewritten. During the encryption/decryption process the file system is left in a mixed state where Disk Utility First Aid and data recovery apps will not be able to work on the drive. Changing Filevault on/off will usually cause a problem if this is being used as a troubleshooting step.
I could manually move all the files over to an external drive piece by piece while on battery power but this is not ideal.
You can try using a third party app like Carbon Copy Cloner where you can select or deselect folders to copy which may help make the process a bit easier.
So my question is one of the following depending on what ideas you may have -
-How can I force file vault to sort itself out
-How can I stop the laptop resetting when plugged in so that filevault might actually sort itself out
You cannot until you resolve the power issue which most likely will require a hardware repair assuming the charger is not at fault. I don't know whether removing the SSD and connecting it externally to another Mac will allow the process to finish. If you have access to another 2015 laptop, then you could try moving the SSD to the working laptop to allow Filevault to finish decrypting.
-How can I get the most files and preferences onto an external HDD
See my mention of Carbon Copy Cloner above.
