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ATI Cloning | 1st Reboot | Error: GPT-formatted disk. Legacy boot not supported.

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Holy hell! I've been an ATI user for >10 years and have cloned countless drives. And, contrary to the thousands of warnings herein, I've always run the clone process from within the source windows environment. Never had any trouble, so have never had cause to come across these VERY IMPORTANT WARNINGS AGAINST DOING THIS VERY THING! So: Win7Pro Cloning from 1TB old skool to 1TB Samsung SSD Used manual clone steps, ATI requested the usual reboot to begin the process. Got the glorious "GPT-formatted disk. Legacy boot no supported." upon reboot. So this is, as I understand from this forum, simply that ATI wrote its temporary boot loader (Linux?) to get the process going, and my system won't permit ATI to boot. Drive is otherwise TOTALLY fine; I can see all my data. BUT. How in the heck can I undo that temporary ATI boot instruction and get things back to normal? I've been reading through this entire(?) forum and have found a couple similar situations, but no definitive solution. I'd really like to avoid complete reinstall and restore. And, YES, I will boot from special ATI media on my next attempt! (The stacks of warnings have been internalized, I promise!)

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Michael, welcome to these public User Forums.

To put some things here into context.

If you start a clone from within Windows, then any restart will use the same BIOS boot mode as your host Windows OS uses, so if the host uses UEFI / GPT that is what will be used for the clone too.

If you boot from the Acronis Rescue Media to perform a clone, then the BIOS boot mode will determine what the target clone drive will use.  So booting in Legacy mode gives a legacy clone, and booting in UEFI mode gives a UEFI / GPT clone.

See KB 59877: Acronis True Image: how to distinguish between UEFI and Legacy BIOS boot modes of Acronis Bootable Media

Note: you may need to check that your BIOS settings allow for booting in Legacy / CSM mode if this is a UEFI BIOS computer, and you may also need to turn off UEFI Secure Boot temporarily for a Legacy boot to work on some machines such as Acer laptops.