It is known to us that C drive is very important to the computer.
If the C partition is running out of space, it will make a big effect on the property of
the whole system, even the speed of the operation. So, keep C drive a full space is
truly necessary, and its neighbor D drive will give a big help to extend its volume.
Why Should We Merge C Drive and D Drive?
When the C partition hasn’t enough space, we must figure out a way to extend it.
There are many ways to extend it. For example, wipe the trash files on the partition
to reduce the using space or extend the whole volume by taking place from other
partitions, such as merge C drive and D drive. Most people know that change the size
of C: will restart the computer. But if we use the partition assistant to do it, we
may avoid this damn thing.
Merge C Dive and D Drive without Restarting Computer
It’s very exciting for clients that extend the C partition without restarting
computer. We can solve the problem easily by taking use of the AOMEI Partition Assistant Professional, an excellent tool which can resize partition, create partition, delete
partition, and so on. What the important, it also supports the free download. The
magic is that under the help of partition assistant, we will merge the two adjacent
partitions into one without changing the data. It’s very convenient for us.
Before we using the partition assistant, there are some tips that we should
follow:
1. Backup the important data by using backup software. Although the partition
assistant will finish the task without losing data, we should keep an eye in case of
the unexpected shut down or the power off.
2. Merge partitions require the two partitions adjacent with each other, or you can move partition so that they are neighbors.
3. If there are some programs running on the partition, the partition assistant will
popup a dialog box to prompt you that it will operate under the PreOS Mode.
Step1.Install and launch AOMEI Partition Assistant. Right-click the
C drive and select “Merge Partition” as the screenshot.

Step2. After this step, it will display the following picture and
you can select the partitions you want to merge. Then, click “OK” to move on.

Step3.Here, you can see that there is only C drive but no D drive.
But, it doesn’t mean that you have finished the job. Click the “Apply” at the left
top.

Clicked the “Apply” will show you an interface which you should click the “proceed”,
and after that, you have finished it yet. But if there is blue words said "Reboot
required" like the following picture, it means the operation will proceed under
PreOS.

In addition, using Partition Assistant to merge C partition and D partition is very
simple and easy. Originally, it can run without restarting the computer and keep your data safe.