To reinstall the Independence Sampler and its Content Library, follow these steps:

1. Go to the Windows Control Panel and uninstall Samplitude Pro X3.
2. Be sure to also remove all Independence installations, folders and files from your system. To do this, go to the Windows Control Panel and select "Programs and Features". Then, uninstall "Magix Independence Libraries Common Files", "Magix Independence Pro 3.3 VST-Plugins" and "Magix Independence Pro Software Suite 3.3". 
3. Delete the following folders:
   C:\Users\All Users\MAGIX\Common\Packages\-
   C:\Users\All Users\MAGIX\Independence Libraries\bundles\-
   C:\Program Files (x86)\Common Files\MAGIX Services\Independence Libraries\-
   C:\ProgramData\MAGIX\Independence Libraries\bundles\- 
   C:\Users\All Users\MAGIX\Independence Libraries\libraries\- 
   C:\ProgramData\MAGIX\Independence Libraries\libraries\- 
   C:\Users\[username]\AppData\Roaming\MAGIX\Independence\Preferences\- 
   C:\Users\[username]\AppData\Local\MAGIX\Independence\Preferences\- 
   C:\Users\[username]\AppData\Local\Temp 
4. Reinstall Independence. 
   

If the program is already installed on your computer, you will be given the option to either "Modify" or "Remove" the installation.
Select "Modify".

The dialog that follows gives you the option of selecting or deselecting additional programs for installation. Select Independence.
Click "Continue" to start the installation.

The plug-in dll's required for Independence (Independence.dll, Independence FX.dll und Independence.Content.exe) should now be located under the following paths:
C:\Program Files\VstPlugins\MAGIX\Independence\VSTPlugin64\
C:\Program Files (x86)\VstPlugins\MAGIX\Independence\VSTPlugin32\

In Samplitude, check under "VSTi" > "Magix Synths" to see if "Independence Sampler" is there. Open it using the "simple" configuration.
Normally, you'll be asked at this point to insert the content DVDs or to download the content from the internet.

If this does not happen, navigate to C:\Program Files\VstPlugins\MAGIX\Independence\VSTPlugin64\ and run "Independence.Content.exe".