Remove a Windows 7 Dual Boot, Part II

Don and Gladys set up Windows 7 to dual boot with an older version of Windows. Now they just want Windows 7.

Part I of this tip explained how to move your data from your old Windows XP or Vista partition to your new Windows 7 partition before deleting the old one. It also included some cautionary advice about removing a partition. Please read that tip before you go on with this one.

And please read this entire tip before you try any of it.

I recommend EASEUS Partition Master for this chore, as no other program I tested did this job reliably. You can use the free Home Edition if you have a 32-bit, x86 system. If you have a 64-bit PC, you'll need the $40 (on sale for $32 as I write this) Professional version.

Before you do anything else, there's one more file you must copy from the old partition to the new one. It's a hidden, system file in the root directory called bootmgr.

In Windows 7, open two Windows Explorer windows, one to C: and the other to your old partition's root (probably D:). Select Organize, then Folder and search options. Click the View tab. Select Show hidden files, folders, and drives, uncheck Hide protected operating system files (Recommended), confirm that you really want to do this, and click OK.

Now drag the file bootmgr from D: to C:. When Windows tells you that you need administrative permission, click Continue. Once the file is copied, you should return to the Folder Options dialog box and hide those operating system files (and maybe the hidden files) again, then close both windows.

If you haven't already installed EASEUS Partition Master, do so now. Then load the program. Right-click the Windows 7 partition and select Advanced, then Set Active. Click OK.

Click the Apply button, and let EASUS boot your PC. When the usual dual-boot option comes onscreen, pick Windows 7. Your PC will begin to boot Windows 7, then go into a special EASUS environment where it will make the change.

When it's done, it will reboot. But instead of bringing you to Windows, you'll get an error message. You now have an unbootable PC.

Don't panic. This is expected. Put your Windows 7 DVD into your optical drive and reboot. When asked to do so, press any key.

At the first screen, where you're asked to select a language, press Next. At the next one, where you're asked if you want to install Windows 7, click Repair your computer in the lower-left corner. After a few seconds, you'll be told that "Windows found problems with your computer's startup options," and asked if you want to "apply repairs and restart your computer?" You do. Click Repair and restart.

This time, keep your fingers away from that keyboard when your PC asks you to "Press any key". Windows should boot normally. You can remove the Windows 7 disc.

Once you're back in Windows 7, reload EASUS, right-click the old partition and select Delete. Confirm your decision. Then right-click the remaining (Windows 7) partition and select Resize/Move. Enlarge the partition to fill all the remaining area. Click OK. When you exit the program, click Yes and let it reboot.

Once again, it will enter the EASUS environment and reboot from there.

At this point, you might be finished. But you may still be asked, every time you boot, which version of Windows you want to load.

To fix that problem, select Start, right-click Computer, and select Properties. Click Advanced system settings. On the Advanced tab, under "Startup and Recovery," click the Settings button. Make sure the "Default operating system" setting is at Windows 7. Then uncheck Time to display list of operating systems.

You've now got a Windows 7--and only Windows 7-machine.

Changed January 7: I have altered the first two paragraphs to emphasize the importance of reading Part 1 first.

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