I have a Samsung SSD with old-style MBR partitioning and a Windows 8.1 install.  I would like it to have a new-style GUID / GPT partition.  Is there  a procedure for doing this conversion?

Can I take an image of the Windows partition, change the partitioning to GPT, install the image, and expect it to work?  Or, maybe there's some tool to directly convert without needing to reinstall an image?

If not, I guess I'd have to reinstall Windows.  Are there any tips for rebuilding a Windows system based on a previous one?

Details:  This is, of course, a UEFI system.  I want to take just part of the SSD for Windows, and the rest for a fresh Linux install.  This is a system I built myself, and I have the Windows 8.1 pro DVD.  I have some big hard disks on the system to make it easy to take backups.

• Edited by Dan Zerkle 12 hours 51 minutes ago

Update:  I installed an empty drive with the GPT partitioning and restored a system image of the Windows partition to that.

Now, the new drive now has MBR partitioning, and in fact has the same partitioning as the original SSD (with a lot of additional unallocated space).  It does boot!  This is great for recovering from a disaster, but doesn't give me a GPT partitioned drive, so it's not useful right now.

Is there a way to do this without reinstalling Windows?  I'm not eager to re-install all my drivers and applications and then re-configure everything.

diskpart can convert MBR-style to GPT-style, but only if it's empty:
https://technet.microsoft.com/en-au/library/cc732165.aspx

https://technet.microsoft.com/en-us/library/cc725671.aspx

There are several important differences relating to system/boot drives, and those are not readily dealt with in a simple manner.
This is primarily why the MBR vs GPT decision, much like the 32bit vs 64bit decision, and the BIOS vs UEFI decision, are important choices to make BEFORE installing the OS. Migrating from one, to the other, is typically "destructive" (wipe-and

Thank you for this information.  Unfortunately, the SSD came with MBR partitioning, and I put Windows on it before I heard of UEFI and GUID/GPT.  The Windows installer never mentioned anything, either.  Maybe it should.

I do understand how to completely wipe the system, change the partitioning, and re-install Windows from scratch.  That is my last resort.

What I really want is to avoid a manual re-install of all my applications and drivers and then all that configuration and those updates.  I thought a system backup and restore would let me do this.  Maybe not.  Any tips?

• Edited by Dan Zerkle 8 hours 55 minutes ago

Just like the Windows Disk Management, Diskpart Command can only realize the conversion between MBR and GPT with a great data loss. When you want to convert the system drive to GPT, they have to make sure that the mother board should support the UEFI mode. If the mother board only support BIOS mode, it can not boot the operating system on GPT hard drive. So i my veiw, you can choice AOMEI Partition Assistant ,which not only supports to convert non-system disk (data disk) from MBR to GPT without losing data, but also supports for converting system disk from MBR to GPT or GPT to MBR.