How to Extend C Drive in Windows 7 When You Have No Space

When you are running out of space on boot partition, this post shows how to extend C drive in Windows 7. Most of the time C drive will be the system and boot partition, extending these type of partitions was not easy in earlier Operating Systems ,but Windows 7 supports extending system or boot partition without any third party tools with built in disk management.

It’s recommended to take backup before continue following steps, but it never fails.

In two ways you can extend C drive in Windows 7.

1) Extending to unallocated space

2) Mounting in to empty NTFS folders in different partitions.

None of the methods require to convert disk to ‘dynamic disks’, so do it with basic disk.

Few Issues and Important Considerations

1) If you have two partitions C and D, D partitions should be deleted to create unallocated space next to C drive.

How to Extend C Drive in Windows 7

Make sure to take backup of your data on D before deleting it.

2) If you have 80GB hard disk and full space allocated as C drive then extending feature will not work. It requires empty space next on same physical hard disk. In this case we can use empty NTFS folder from different physical disk.

See Also,

How to Split partitions in Windows 7

Lets Do it

1) Let me extent C partition in above example. ‘Extend Volume’ option is disabled in disk management when I tried without deleting D.  Take a full backup and delete the D volume.( Right click on volume and select delete volume)

How to Extend C Drive in Windows 7

Now, right click on C drive and select Extend volume.

How to Extend C Drive in Windows 7

Add the available unallocated space in next screen. You can adjust the space to merge with C drive. Here I selected entire unallocated space.

add_free_space After successfully merged the free space, here is the extended partition.

How to Extend C Drive in Windows 7

Note: Once you allocated entire physical hard disk to C drive and no more partitions available next to it then ‘Extent Volume’ will be disabled. You can’t extend C drive to other physical disks.

Follow NTFS folder method to extend c drive to other physical disk partitions.

2) Lets assume, again my C drive is full and no partitions available on the same disk. So, I’m going to use NTFS folder method to extend it to other basic disk.

create_empty_folderNow, right click on C drive and select ‘Change Drive Letter and Paths’ option. Press Add and browse for the empty folder created in different partition. I created empty ‘C_drive’ folder on D drive physical disk.How to Extend C Drive in Windows 7You can’t see the immediate changes. If you go to D drive and look for the empty NTFS folder used to mount C, it appears as below.

mounted_folder Opening this icon will take to entire C drive on other disk.

Now C partition space = C drive + Free Space on D

I’m sure these two methods will be helpful to extend C drive in Windows 7 when you are running out of space.

Good thing is, it doesn’t require to convert to dynamic disk. Still if you don’t want to delete the next partition, then use empty NFTS folder to mount.

Do you face any issues on this? Share it here.


  1. says

    After completed “Follow NTFS folder method to extend c drive to other physical disk partitions.” section. I download some of software and it automated save in C drive. The system noticed me that C drive is full space therefore the system couldn’t download extra software in C drive. Please advice extra step how to extend in C drive.


  2. Dart Eksem says

    Far better solution: Create in drive C a Symbolic Directory Link that points to a folder in another drive. Then put your data in this symbolic folder, and they will actually be in the second drive, but accessible from drive C.

  3. king says

    i cant click on extend volume,even i delete one of my partion and want to extend the volume of C drive.!! what to do?

  4. Tom Nguyen says

    I can’t extend it , because my computer had 3 volumes, It won’t alllow you to extend it. Someone have any ideas?

  5. emad says

    brilliant, i didn’t even find such professional explanation on Microsoft’s website. Thank you so much