Hi Scott. I'm Greg, 10 years awarded Windows MVP and Volunteer Moderator, here to help you. I would use the choice of all experts free Macrium, which would allow you to drag each partition from the source drive, then before applying it click the Drive Tools link on C to extend it over to take up the extra space, while moving the Recovery partition over. I've never seen it estimate the d Click Yes in the confirmation prompt. Next, right-click on the E: drive, and select Extend Volume. Then, click Next to continue, enter the amount of unallocated space that existed earlier in the text field, and follow the on-screen instructions to merge. Once done, right-click on the remaining unallocated space (previously the D: drive), and Alan Russell. You cannot combine space from two separate physical disks. You have two choices: 1. Replace your C drive (disk 0) with a larger disk, or. 2. Move some of the files from the C drive to a D drive on disk 1. Be very careful moving files from C to D; moving the wrong files can render your PC inoperable. I am trying to replace the hard drive on a Lenovo Ideapad 100s. The new disk is a WD3200BUCT and is seen in BIOS, however when starting install, windows set up shows Drive 0 Unallocated space Total size 0 and free space 0 "windows cannot be installed on this drive" (the partition is too small). Put the mouse on the partition and drag it to the left or right to move the unallocated space. You can repeat Step 1 and 2 to move the unallocated space to the desired location. Step 3. Click "Execute Task" and "Apply", it will execute the operations to add the unallocated space into the target partition eventually. 2. English Want to merge unallocated space in Windows 10 to make full use of the disk space or solve low disk space issue? This post will show you two cases: how to merge two unallocated spaces (3 situations) and how to add unallocated space to C drive in Windows 10 without losing data. On This Page : Why Need to Merge Unallocated Space Step 1. Press Win + R keys to open the Run box, and then type cmd in it and press Enter. Step 2. In the Command Prompt window, type diskpart and press Enter to access the utility. Step 3. Type the following commands one by one and hit Enter after each one to merge the USB partitions into unallocated space. 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. vuyrdKE.