How to Extend a Disk Partition in Windows Vista
Like in most administrative tasks, you must logged on as an Administrator.
1. In Windows Vista, go to Control Panel --> System and Maintenance > Administrative Tools, or on the My Computer context menu. Select Computer Management. In Vista, if you are prompted for an administrator password or confirmation, type the password or provide confirmation.
2. Next, scroll down till you get to the Storage section, and in it go to the Disk Management console.
3. Select the disk you want to extend, for example Drive C. Note: Extending any volume is fine as long as you have additional unallocated free space on that same physical hard disk . Note that you can also extend the partition beyond the physical disk it is located on. This is useful when you run out of space on that physical hard disk, and have brought in a new physical hard disk that you wish to use. However, unlike using that new disk as a totally new partition by itself, this disk (or part of it) becomes a part of a partition located on the first disk. While useful in some cases, this scenario might cause fault tolerance issues, because this extended partition is NOT fault tolerant, and if something happens to one physical disk, all the data on that extended partition becomes unavailable, and data loss can occur. In any case, such an extended partition can contain an unlimited number of logical drives.
4. Right-click the disk and select Extend Volume.
5. Click Next.
6. Windows Vista tell you how much space can be added to the existing partition. You can manually enter the amount of space you want to add by changing the "Select the amount of space in MB" values. However note that you cannot enter a higher value than the value already present. As noted above, if you have additional physical hard disks that have unallocated free space, you can add that space up and further extend the partition to span multiple disks. Again, be warned, this configuration is NOT fault tolerant. In case one of the disks malfunctions, you will lose your data.
7. The process will finish quite quickly, and a reboot is NOT required.