Can I retrieve data without a Time Machine from an erased iMac?

WhatisIcloud wrote:

We performed migration assistant from a small Mac Airbook to restore an imac computer (#1) whose hard drive we had to wipe. Unfortunately the other functioning imac (#2) in the house with the same apple id was wiped and the migration took place on that one too. WIthout Time Machine set up is there anyting we can do to get the functioning imac's (#2) info back?

[Re-Titled by Moderator]

It sounds like you accidentally (unintentionally) "wiped" iMac #2 and migrated from the MacBook Air to iMac#2. And now you want to restore iMac #2 back to how it was ... but you have no backup to restore from?

With no backup of iMac #2 to restore back to it, your only recourse would be to take the iMac #2 to a data recovery service. If this was a very old iMac and its internal drive was the older HFS+ format, SOME of the original files might be recoverable. But most likely it has been using APFS format, which means this is almost impossible to do. In addition, the unintended migration from the MacBook Air has already written data over the original data in that iMac #2. The data recovery services can cost $thousands and it sounds like in this instance the chances of success are very low.

As others have pointed out, having backups is essential for unexpected mishaps (you have just experienced one). I have ~ 3 physically separate backups of all valuable computers/files plus store important items in the cloud (a combination of iCloud Photos, iCloud Messages, Dropbox, online backup, etc.).

Even having a Time Machine backup connected at all times is not immune. I have seen (once) a power surge damage a computer plus the backup drive connected to it. So if that happens, the originals plus the backups can all vanish in an instant. I have seen homes damaged by flood and by fire. And then there is always a chance for human error (what happened in your case).

Back to your original question: if you truly "wiped" the drive (erase/format) and have no backup, I believe that data is not recoverable, especially if files have also been written onto the erased drive.

Doing it yourself will not be possible, you could consider going to a recovery specialist service and see what they can do for you, but it is quite expensive $1000 or more

WhatisIcloud wrote:

Unfortunately the other functioning imac (#2) in the house with the same apple id was wiped and the migration took place on that one too.

FYI, iCloud is not a backup option for Macs. Any catastrophic edit or deletion from iCloud on one device will occur on all of the other devices connected to the same AppleID.

WIthout Time Machine set up is there anyting we can do to get the functioning imac's (#2) info back?

Did you have any type of backups using any third party apps or even a manual backup by manually copying files to external media? Perhaps you sent some files to someone else who may still retain a copy.

Was this over wifi?

If it happened as you said, I don't see anyway to get the data back.

·       Always connect your old Mac's Time Machine External Hard Disk prior to startup, this will allow a migration from your TM backup and it will be dead simple! When you start the new Mac for the first time it will startup Setup Assistant (SA), SA will get to a point where it asks if you are migrating from another computer, select Yes and follow the on-screen prompts and it's done! It is that simple! This is the easiest, quickest and most reliable method to migrate from the old Mac to the new Mac is to simply connect the old Mac's Time Machine External Hard Disk to the new Mac using a USB cable before you turn on the new Mac. 

·       NOTE 1: You will likely need a USB A to USB C adapter, you can find them on Amazon for $10 or less.

·       NOTE 2: If you have already done SA on the new computer then simply connect the Time Machine External Hard Disk using a USB cable and launch Migration Assistant (MA) which is located in Applications - Utilities - MA. Then follow the on-screen prompts.

·       The ONLY difference between MA and SA is MA will create a new user account that you need to log into.

Both SA and MA migrate applications (not 32 bit apps), data files & settings. They do not migrate Mac OS itself. Some professional apps such as Adobe and Microsoft apps may require re-installing their apps as they will not allow them to be migrated. As long as you kept the security keys for installing their apps, it is not an issue. 

Finally, never EVER use Wi-Fi when doing Setup Assistant or Migration Assistant. Why, it simply fails in most cases. Please read and follow the directions in Setup Assistant and Migration Assistant. If you do not have a Time Machine backup of the older Mac then create one! If you are not aware of Time Machine, please read Back up your Mac with Time Machine and finally if you need an External Hard Disk to use as a Time Machine External Hard Disk then many experience users on these forums prefer the OWC Mercury Elite Pro due to it's reasonable price, high level of quality and ease of use. 

Then take the ship back to port, outfit it correctly this time and then you can sail in calm seas. IF you don't your voyage will be rough and the crew will get seasick.