Compare with Windows Server 2000 and 2003, one of the improvements in Windows Server 2008 Disk Management snap-in is that it provides two new functions "Extend Volume" and "Shrink Volume". So you can extend C drive in Windows 2008 with Disk Management. On the other hand, there are some restrictions you may encounter as follows:
Restriction 1: You can not extend C drive in Windows 2008 if there is no contiguous unallocated space on the right side of C drive. In such case, the "Extend Volume" option will be greyed out.
Restriction 2: You can not extend C drive in Server 2008 by shrinking data partition behind it. Because "Shrink Volume" feature only generates unallocated space on the right side of the partition you shrink, e.g. [C drive][D drive][unallocated space that shrunk from D drive]. In such case, you must backup D drive and delete it or create a new partition with the unallocated space -> migrate the data in D drive to the new created partition -> delete D partition -> extend C drive. ( how to merge non-contiguous unallocated space to C drive).
Solution 1: Extend C drive with Windows Server 2008 Disk Management snap-in
As mentioned above, in order to extend C drive in Windows Server 2008, you have to backup and delete the partition behind C drive. For example, the partition behind C drive is D drive.
Step1: Right click "Computer" > "Manage" > "Storage" > "Disk Management".
Step2: Right click D drive and select "Shrink Volume". After that, right click the unallocated space and select "New Simple Volume".
Step3: Backup D drive to the new created partition. Then, right click D drive and select "Delete Volume".
Step4: After deleting D drive, there will be some contiguous unallocated space on the right side of C drive. Right click C drive and select "Extend Volume".
Solution 2: Extend C drive in Windows Server 2008 without deleting - Recommended
Generally speaking, it is a headache for most people to backup data and delete partition which are time-consuming and risky. Partition Magic Software is another choice which allows you to extend C drive in Windows Server 2008 and 2008 R2 SP1 without deleting partition. Although Norton Partition Magic is considered as the most well-known partition software, it is not compatible with Windows Server operating system. As Partition Magic or Disk Management alternative, Partition Assistant Server Edition is the optimum selection.
Tips: You can free download demo version and have a try.
Step1: Launch Partition Assistant Server. On the disk map, it allows you to view the detailed information of all disks and partitions. Then right click partition D and select "Resize".
In the pop-up window, drag the left slider bar rightwards to shrink D partition, and then click "OK".
Step2: After the step above, there will be some contiguous unallocated space behind C drive as shown below. Select C drive and drag the right slider bar rightwards to extend it.
Step3: Click "Apply". The changes that list in the "Pending Operations" will be successfully completed.
In summary, in order to extend C drive in Windows Server 2008, there should be contiguous unallocated space on the right side of C drive, otherwise, you cannot extend C drive. With convenient and reliable Partition Magic Server 2008 Software - Partition Assistant Server Edition, you can extend C drive in Windows Server 2008 without the need to backup data and delete any partition.
Tips: For Enterprise users, Unlimited Edition provides unlimited usage within one company to save money, namely, you can install it on multiple machines in your company to maximize business productivity whilst minimizing the total cost of management.
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