In order to activate the Full Text Search please configure Acrobat or Acrobat Reader:

1.  Start Acrobat or Acrobat Reader whichever version is default in your system.

2.  Acrobat 5.0 or Acrobat Reader 5.0: Please set preferences as below by choosing Edit > Preferences > General. In the Options section, deselect "Display PDF in Browser"

3.  Acrobat 4.x or Acrobat Reader 4.x: Please set preference as below by choosing File > Preferences > General. Deselect "Web Browser Integration"

4.  Click OK, and then exit from Acrobat or Acrobat Reader.