How to Extend Primary Partition on Windows Server 2008 (R2) without Losing Data?

January 30, 2018

With the help of AOMEI Partition Assistant Server, you can extend primary partition without data loss for Windows Server 2008 (R2) effectively and securely. It is suitable for Windows Server 2016/2012 (R2)/2003 as well.

Overview of primary partition

A primary partition is the volume where operating system can be installed. For MBR style disk, it can hold up to four primary partitions. For GPT style disk, it is able to hold 128 primary partitions at least. Active partition is based on primary partition. There can be 4 primary partitions and only one active partition. Any primary partition can be set as active partition that contains boot loader to load operating system. A primary partition can be a drive that operating system is installed on or a drive that stores regular data. General speaking, only one primary partition is necessary, which is known as C: drive.

When need to extend primary partition Windows Server 2008 (R2)?

As time goes on, more and more applications have been installed on Windows Server 2008 (R2) hard drive and the primary partition is lack of spaceWhat’s worse, the warning “Low Disk Space” may present. You can find that the running speed of machine is lower and lower and the applications even don’t react when you click icon of some applications. In such case, you can  extend Windows Server 2008 (R2) primary partition to get the machine back to normal situation. The next part will show  how to increase primary partition size on Windows server 2008 (R2) primary partition.

Extend primary partition on Windows Server 2008 (R2) via Disk Management

Disk Management is a tool built in Windows Server 2008 (R2) and it allows you to shrink and extend partition. It is available to quickly access Disk Management by “pressing Windows +R” and typing diskmgmt.mscand hitting “Enter”. You can increase the primary partition size when there is unallocated space just right behind the primary partition; otherwise, you will find out that Windows Server 2008 (R2) “Extend volume” grayed out. Here recommend you to apply proper third party software to extend Windows Server 2008 (R2) primary partition.

Extend Volume Grayed Out

When you’re insisting to extend primary partition C: drive with Disk Management, you can refer to the following instruction.

1. In order to get unallocated space right behind the primary partition C: drive, you have to delete primary partition D: drive (backup important data before deleting).

PS: If the partition right behind C: drive is an extended partition, you have to delete all the logical drives on the extended partition. Then delete the extended partition to get an unallocated space for extending C drive.

Delete Volume

2. Then, it is able to increase C: drive size with Disk Management. Click C: drive and choose extend volume.


  • Both free space and unallocated space and unallocated space refer to storage space that doesn’t hold data in different ways. Free space can’t be used to extend primary partition and unallocated space can’t be applied to extend logic partition.

  • If you are familiar with Windows command prompt, you can extend partition with Diskpart. But this also demands an unallocated space contagious to the partition you need to extend.

 Extend primary partition Windows Server 2008 (R2) with great disk management tool

Obviously, it is bothering and time-wasting to extend C: drive via Disk Management or Diskpart on Windows Server 2008 (R2) if there is no contiguous unallocated space right behind the primary partition that you want to extend. Fortunately, even in that case,AOMEI Partition Assistant Server can allow you to extend primary partition without losing data. The following part will show you how to extend Windows Server 2008 (R2) primary partition with AOMEI Partition Assistant at length

First of all, what you should do is to install AOMEI Partition Assistant Server and launch it.

Step 1.To increase primary partition size on Windows Server 2008 (R2), right click the primary drive that you want to extend and select “Merge partitions”.

Merge Partitions Windows Server 2008 R2

Step 2. Tick the box before “Unallocated” to extend C: drive. Then, click “OK”.

Add Unallocated Space to Primary Partition

Step 3. Check the pending operations and click “Apply” to implement this task.

Extend Primary Partition Server 2008 R2


  •  “Free space” and “unallocated space” shall be marked as the same type-“unallocated”.

  • AOMEI Partition Assistant can merge unallocated space with C: drive no matter whether the unallocated space is right behind the primary partition or not.

  • If there is no unallocated space or free space on the disk hard drive, you can shrink partition to get it. Or you can just merge C: drive and the partition right next to it (here is D: drive); the data on D: drive will be reserved in the form of a folder on the merged partition.

  • You can use the function of “Allocate Free Space” to flexibly take advantage of unallocated space.


There is no doubt that AOMEI Partition Assistant Server can extend primary partition on Windows Server 2008 (R2) effortlessly and securely. As an excellent disk management tool, apart from extending primary partition, it is built with many other functions such as move partition, create partition and convert MBR to GPT/GPT to MBR. What’s more, with high compatibility, AOMEI Partition Assistant can work with Windows Server 2016/2012 (R2)/2008 (R2)/2003; with user-friendly interface, it is easy to use even for a green hand. All in all, AOMEI Partition Assistant is powerful and comprehensive software that can help you a lot in disk management.