I've downloaded abobe 9.4 ...
What exactly did you download - Adobe Reader 9.4, or Adobe Acrobat 9.4?
Adobe Reader is free, Adobe Acrobat is not.
If it is something else than Adobe Reader you have installed, uninstall it, then download the free Reader from http://get.adobe.com/reader/
If you need more help, tell us what your operating system is (Windows, Mac OS, Linux).