Q: I forgot my security pin

Read this.

Locked Out, Forgot Lock or Restrictions Passcode, or Need to Restore Your Device: Several Alternative Solutions

A

1. iOS- Forgotten passcode or device disabled after entering wrong passcode

2. iPhone, iPad, iPod touch: Wrong passcode results in red disabled screen

3. Restoring iPod touch after forgotten passcode

4. What to Do If You've Forgotten Your iPhone's Passcode

5. iOS- Understanding passcodes

6. iTunes 10 for Mac- Update and restore software on iPod, iPhone, or iPad

7. iOS - Unable to update or restore

Forgotten Restrictions Passcode Help

            iPad,iPod,iPod Touch Recovery Mode

You will need to restore your device as New to remove a Restrictions passcode. Go through the normal process to restore your device, but when you see the options to restore as New or from a backup, be sure to choose New.

You can restore from a backup if you have one from BEFORE you set the restrictions passcode.

Also, see iTunes- Restoring iOS software.

It's asking for the passcode that you use to lock/unlock iPad.