If the unallocated space is on the right side of the C drive and adjacent to the C drive, you can add the unallocated space to the C drive. Step 1. Right-click "This PC", choose "Manage" option, and click Disk Management to open Disk Management. Then, right-click the C drive and click Extend Volume. Step 2. You can then enter the Extend VolumeStep 1. Right-click "My computer"→"Management"→"Disk Management". Step 2. Right-click the unallocated space, choose "New Simple Volume" from the shortcut menu. Follow the wizard, and click "Next". Step 3. Set the size of the new volume by using the Simple Volume Size. Click "Next". Step 2. Add space to system drive C. 1. Shrink partition and leave unallocated space to extend drive C. Right-click on a partition next to the C: drive and select "Resize/Move". Drag the end of the partition next to the C: drive and shrink it, leaving unallocated space next to the system's C: drive and click "OK". 2.
If you do that, then reboot into Windows after completing the ext4 expansion. Click the Windows start key and type Recovery Drive. Under Settings, click Create a recovery drive. Your computer may ask you whether you would like to open Recovery Media Creator. Click Yes, and tell it to use that new drive letter for Recovery purposes.Extend Volume Option is Grayed Out in Windows Disk Management Console. Open Disk Management console (diskmgmt.msc) and right-click on the partition you want to expand (in my example, it's a logical volume assigned the drive letter C:\).As you can see, the Extend Volume option is grayed out. The fact is that you can extend a volume in Windows only if there is an Unallocated space to the right
Right click on the specific partition you wish to format, select format and then format it. Note: Wherever data is combined in folders on a drive / partition you wish to format, back all that up first and then format. That works for any partition including the primary partition. That should work and be safe to do.
yoyPD.