How to extend system partition in Windows Server 2012 (R2)?

It is not an easy task for many people including server administrators to re-size or extend system partition. Nobody would like to see system failure or data loss after doing this. Actually, it is EASY if you use right utility and follow the correct steps. Today I want to share how to increase system partition size in Windows Server 2012 R2 without reinstalling Windows or losing data. Remember, data is most important to a server, so back up before any operations. Select a reliable software to extend system drive, a bad designed program may cause system boot failure or data loss!

What is system partition

Many people do not know the right meaning of “system partition”, maybe it is the partition (C: drive) where Operating System is located. Let’s open Windows built-in Disk Management, there you’ll see connected disks and detailed information of each drives.

As you see, the partition marked as System is not C drive but another System Reserved partition. The system partition is the primary partition that is used as the active boot partition. System partition must be located on the disk where the computer boots from. One disk can only have one active system partition. System partitions refer to disk volumes containing defined files for the boot of Windows.

In short, system partition is used to boot Windows, while C drive (marked as Boot) is where Windows located.

Okay, I don’t want to speak like a book, as the comprehension of most people, system partition is system C: drive. (lol)

Low Disk Space in system partition

It is the most common issue in Windows platform and the reason why increasing system partition size. Different with previous version Server 2008, in Windows Server 2012, you won’t see “Low Disk Space” warning by default. Instead, when system C drive is running out of free space, it becomes red when opening My Computer or Explorer. In this situation, extend system partition as fast as possible, nobody would like to see system stuck or crash. (you may enable low disk space alert in Server 2012 when system partition is running low)

How to extend system partition

There are two choices: Windows built-in Disk Management snap-in or 3rd party partition software. Due to limitations of Disk Management, I recommend using 3rd party professional partition resizing software. However, some people insist on using Windows built-in utility, then follow the steps below.

Extend system drive under Server 2012 Disk Management

From Microsoft document, to expand a drive under Disk Management with Extend Volume there must be adjacent Unallocated space, so you CANNOT extend system partition by shrinking other data drive. (about Extend Volume greyed out in Server 2012)

The only way in Disk Management to extend C drive is deleting the adjacent data drive to get Unallocated space.

Applications and services running from this drive stop working after deleting. This operation cannot be undone.

If you insist on extending system partition by deleting a data drive, continue the steps below. Otherwise, see how to resize partition with 3rd party program.

Step 1: Backup or transfer all files in drive E to other device. Right-click drive E and select “Delete Volume…”, it will be changed to free Unallocated after deleting.

Delete volume

Step 2: Right-click drive C and select “Extend Volume…”

Extend Volume

Step 3: Select the available Unallocated space and click Next to continue.

Available space

Step 4: Confirm the operation, click Finish to proceed.

Complete extending

System C: drive extended by using all space of data drive E.

partition combined
Some people like to use Windows built-in utility, but I do NOT recommend a solution in destructive way, why not increasing system partition size without deleting?

Steps to extend system partition on Server 2012 with ease

Step 1: Download NIUBI Partition Editor, right click D: drive and select “Resize/Move Volume“.

Drag to resize

Step 2: In the pop-up window, drag the left border rightwards to generate free Unallocated space.

Shrink volume

You may also input a value for the Unallocated space directly.

Drag to resize

Click OK and back to the main window, where you’ll see 20GB Unallocated space created behind C: drive.

Unallocated space

Step 3: Drag the right border rightwards to hold the Unallocated space.

Drag to resize

Hold unallocated space

Step 4: Click OK and back to the main window, where you’ll see C drive extended to 60GB by robbing 20GB free space from D. Press Apply on top left to execute, done!

Partition resized

Video guide to extend system partition on Server 2012

This server partition software integrated unique Roll-Back protection technology, which is able to roll back the server to the status before resizing automatically and rapidly, even if power failure or any other hardware issue occurred, so you don’t need to worry about Operating System and all data safety. Furthermore, it is 30% – 300% faster than ANY other tools by strictly testing, because of its unique file-moving algorithm.

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