Solution 1:

WARNING YOU CAN REALLY MESS UP YOUR COMPUTER IF YOU DON'T FOLLOW THESE INSTRUCTIONS CAREFULLY, IF YOU DON'T FEEL COMFORTABLE DOING THIS THEN I SUGGEST YOU DON'T, ALSO I SUGGGEST YOU BACKUP ALL YOUR DATA BEFORE YOU BEGIN

  1. go to start and type cmd (this is called command prompt)
  2. In command prompt type diskpart and hit enter
  3. type list disk and hit enter
  4. From the list of disks find the one you want to work with (I believe in your case there is only one so it should be easy)
  5. once you find the drive you are looking for type select disk <numberofdrive>
  6. now type list partition and find the partition you want to work with
  7. once you have identified the partition in question type select partition <numberofpartition>
  8. now type delete partition (WARNING ONCE YOU DO THIS THERE IS NO GOING BACK) and hit enter , if it says "cannot delete a protected partition..." use delete partition override (Note you will also have to repeat these steps with the partition in front of the recovery partition if you plan on extending the system volume)
  9. once it is finish type exitand hit enter
  10. go back to diskmanager
  11. right click on the C: volume and click extend

Solution 2:

To delete a partition that refuses to delete, use diskpart in the Command Prompt for this operation:

  1. First launch Command Prompt, or press Windows Key + R to bring up Run. In Run, type "CMD" without the quotes. Make sure you are Admistrator.

  2. Command Prompt should pop up. With command prompt open, type diskpart

  3. In the User Account Control, either sign in as an admin if you are already not or press yes if you already are.

  4. Another command prompt window should come up, this is the Windows Disk Partition Editor. In this command prompt type list disk.

  5. A list of all your disks should come up.

  6. Then, select the disk you are using (in this case disk 0) by typing select disk 0. Disk 0 should be selected.

  7. Then, to list partitions, do list partition it will then bring up a list of all the partitions. Then to select the partition you want to delete, find the number of the partition (like Partition 1 or Partition 2 or whatever partition one of your recovery partitions are) and type `select partition '. This will select your partition.

  8. Then, to delete the partition that you cannot delete in the graphical user interface, type 'delete partition override'. This command force deletes the selected partition (the recovery one you selected).

  9. Repeat steps 7-8 for the other ones.

  10. In the screen you started with (out of the command prompt now) you should notice a black volume on your C: Drive. Right click on the and click New Simple Volume.

  11. Proceed