How to extend system drive partition (C:) to get more capacity

When you are unable to make changes to partitions using Disk Management below are partitioning programs you can use.

EASEUS Partition Master (free):

Includes Partition Manager, Disk & Partition Copy Wizard and Partition Recovery Wizard for Windows XP/Vista/Windows 7 (32 bit and 64 bit). It allows users to Resize/Move Partition, Extend System Drive, Copy Disk & Partition, Merge Partition, Split Partition, Redistribute Free Space, Convert Dynamic Disk, Partition Recovery and more. Be careful, re-sizing partitions is usually safe but errors can happen, and always backup anything important before modifying partitions on your hard drive.

http://www.partition-tool.com/personal.htm

Paragon Partition Manager (free):

A good program for making general changes to hard drive partitions while Windows is running. Create, delete, format, and resize partitions with this program. It can also defragment, check file system integrity, and more. Be careful, re-sizing partitions is usually safe but errors can happen, and always backup anything important before modifying partitions on your hard drive.

http://www.paragon-software.com/home/pm-express/download.html

Gparted Boot Disk(free):

If you can't make the changes you want with Windows running using a Gparted boot disk to change the partitions is a good solution. If you will be changing the main Windows partition, or a partition with important info, backup anything important - it's not common, but things can go wrong. Altering the partitions can be risky, be careful and know what you are doing - there is no Windows safety option when using this - if you tell it to format the Windows partition it will do so and delete the entire Windows installation. Depending on what you are doing it can take from a few minutes to a couple hours. Download the ISO and burn it to a CD.

http://sourceforge.net/projects/gparted/files/gparted-live-stable

How to use:

http://www.dedoimedo.com/computers/gparted.html

If after altering the partitions Windows 7 data/files are still there but Windows won't boot the following may help:  

Try Repairing The Windows 7 Installation

1. Insert the Windows 7 DVD and restart your computer
2. Boot from the DVD.
3. Choose your language and click Next.
4. Click Repair Your Computer and then select the operating system you want to repair.
5. Click on the Startup Repair link from list of recovery tools in System Recovery Options.

If that doesn't fix it:

1. Insert the Windows 7 DVD and restart your computer
2. Boot from the DVD. If prompted, press any key to start Windows from the installation disc.
3. Choose your language and click Next.
4. Click Repair Your Computer and then select the operating system you want to repair.
5. Select Command Prompt and try the following commands (a single command might work, or you may need to use multiple commands depending on the exact problem):

bootrec /fixMBR

bootrec /fixBoot

bootrec /rebuildBCD

Note: there is a space before the /

Have Questions About Installing Windows 7?

FAQ - Common Windows 7 Installation Questions & Answers