Converting Master Boot Record to GUID

[Lemar]

Hello folks,

I am new to Mac and recently (May 2014) bought a Macbook Pro (i7 processor, 16 GB memory, 251 BG SSD).

I have set aside 40 GB for Windows 8 (Bootcamp) and the rest is used for Mac. But recently I realized that I barely use Windows and hence want to get rid of it. I tried removing Bootcamp using Disk Utilities. But whenever I do that, the minus and plus button are greyed out and I'm unable to do so.

Secondly, I want to install the new OS X Yosemite and downloaded the file. After going through the process, I get the message that neither of my disks are using GUID partition scheme, so I can not install the software update. I checked the main disk format and it turns out to be Master Boot Record. I went through all online articles regarding this matter, but to be honest, they were pretty confusing. I could not find a clear way of converting MBR to GUID.

Could someone kindly explain how to tackle these issues?

Any input will be highly appreciated

P.S. Few days ago I bought a 2 TB Time Capsule to backup all my files in case something goes wrong.

 

[bobtomay]

Removing the windows partition is done the same way you added the partition - with Bootcamp Assistant - not with Disk Utility. Here is a walkthrough - link.

After you have your backup done...

Try removing the Windows partition first and then try installing Yosemite.

Let us know what happens from there.

 

[Lemar]

Hello bobtomay,

I forgot to mention that I have already done that. The thing is, the option which says ''install or remove Windows 7 or later'' is greyed out.

 

[bobtomay]

Then the partitions have already been messed up or you haven't installed the latest bootcamp drivers.

I'd verify there is no update for the bootcamp drivers first. If so, then try removing it again.

To use Disk Utility for making changes to the drive, you need to boot the machine holding down the command and R keys - select Recovery and then Disk Utility.

If you can't delete the windows partition from there and enlarge the OS X partition to take that space - Next you're going to need to show us a pic of Disk Utility - with the hard drive selected on the left - on the 'Partition' tab and the windows partition selected on the right...

You can post a screenshot by clicking the 'Go Advanced' button below the Quick Reply box and then scroll down to Manage Attachments. Close the window to go back to your post after selecting and uploading the pic.

(Something is wrong or already played with, because no new Mac arrives with a MBR instead of a GUID partition scheme.)

 

[Lemar]

I did not know about the command R function of the Mac and did as you had instructed. I managed to delete both partitions and make two new ones with GUID scheme. Then I backed up my Mac using Time Capsule. It worked perfectly fine (though took half of my day )

I would really like to thank you for your swift comments and advice

All my problems are solved as it appears. Now I am busy updating my OS to Yosemite.

Thank you once again.