How do I boot from carbon copy clone on external drive

My iMac won't boot up (grey screen or "read file failed.status 7,mach_kernal) . I've tried to search for this answer but I'm not getting the idiot instructions on how, exactly, to boot from my external hard drive-nor what to do next. Am in the middle of an important work project so I really need to sort this.

The law of s*d strikes again. While keying this, on my iPad, my iMac went to a blue screen and then gave me the login window and appears to be working. My question remains though for next time-meanwhile I really need to know what to do. Restore permissions? Run Onyx? Look into changing my hard drive ? Buy new iMac? Make new CCC copy?. I do have Time Machine backups BTW?

UPDATE - On checking my system is running on a backup from October last year. No files updated/created since then are there. Need help Urgently!!!

All or any assistance gratefully received. Thank you.

Further update. My time machine is only showing backup for 29 Oct 2019. Please tell me that I can recover from this.

Anyone? Sorry I appear impatient but I really, really, need to amend some docs for my wife to present later this pm. Will it be sufficient in the short term to select mac HD on Time Machine backup and press 'Restore'

I'm not sure I have anything useful to add (which is why I didn't post earlier). Not sure I would do the restore thing at this point at the risk of making things worse.
I have my TM backups on a Seagate External and I am able to use finder to browse through them. If you can do that, I would opt for that to manually look for your files.

Razormac said:

I'm not sure I have anything useful to add (which is why I didn't post earlier). Not sure I would do the restore thing at this point at the risk of making things worse.
I have my TM backups on a Seagate External and I am able to use finder to browse through them. If you can do that, I would opt for that to manually look for your files.

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Finder only sees the Oct 2011 backup on time machine volume, but if I run Time Machine I see all recent backups.

Sawday said:

Finder only sees the Oct 2011 backup on time machine volume, but if I run Time Machine I see all recent backups.

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You can't scroll through to the files you need in TM and restore them individually?

EDIT: I understand about seeing only the single Backup File (assuming Oct 11 is the origin date) but if you double click can you browse through it (I can do this on mine)?

Razormac said:

You can't scroll through to the files you need in TM and restore them individually?

EDIT: I understand about seeing only the single Backup File (assuming Oct 11 is the origin date) but if you double click can you browse through it (I can do this on mine)?

Click to expand...

Restore individually??? All files created or amended since oct 2011???

In finder- phew! You're right - obviously I panicked - I can click on the backup file and see them all. To proceed though should I restore each top directory in turn (applications, library, system, users etc) , then run updates to get the OS back to where it should be, then what else do you recommend (short of looking into getting a new hard drive) onyx? Restore permissions? Also,for information if not needed right away, just how do you restore a CCC backup?

Honestly, I have never done (or needed to do a restore) other than dragging out individual files (and that has been awhile). And, though I have a bootable CCC backup which I verified to be bootable), I've never pulled anything from it.

Sorry, I have to go back to my original statement of not being much help. Wish I could do more.

EDIT: and to my comment on individual files, I had gotten the impression you were trying to access a few files your wife needed ASAP

Razormac said:

Honestly, I have never done (or needed to do a restore) other than dragging out individual files (and that has been awhile). And, though I have a bootable CCC backup which I verified to be bootable), I've never pulled anything from it.

Sorry, I have to go back to my original statement of not being much help. Wish I could do more.

EDIT: and to my comment on individual files, I had gotten the impression you were trying to access a few files your wife needed ASAP

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Yes I did need access quickly to a few files, so thanks for yor reply on that as that is working (several linked excel spreadsheets spread over three years with a number of formatted auto updated reports. I'm also about to start my own business and since October have all my business forms in various stages of design, sample research reports, business plan, artwork etc.. Losing those would set me back months and that's before I get onto the personal banking files, my fledgling company accounts and databases I maintain for another part of my wife's work.

Quests I'll start restoring all the data files from time machine initially and see if anyone has other suggestions or answers to my other queries. Many thanks for your assistance thus far-this forum is an essential tool when things like this happen!!!

You are welcome!

My hesitation on trying the blanket restore is (since I have never done it) potential data loss. If you have an extra internal HD lying about, may be worth installing it and doing a reformat and clean install of the OS and then migrating from your TM backup to see if you get everything.

Or, if you wait, someone who has actually had experience with TM restore may weigh in. The possible best soloution may be the restore you originally talked about.

The saga continues...I'm restoring all my data files from Time Machine but every now and again I'm getting "The operation can't be completed because you don't have permission to access some of the items". I am using my usual (admin) login. This is happening, for example for the Applications directory under my user name.
Also, and this may be related when I try to run MS Office 2011 Excel (to read one of my newly restored files) it comes up with the initial Office install screen.
Do I carry on restoring everything I can individually (at least by directory) or do I bite the bullet and either get a new internal hard drive or new iMac. Alternatively could I do the following in the short term. My TIme machine backup disk is a 2TB jobby. Can I use 500Mb of that as a surrogate hard drive and run my iMac from that? If that's possible at least it gives me a breathing space.