I think that error occurs because the catalyst driver installation was not totally a success.There must have occured something in between the installation.
So what you could try is,first download the latest drivers for your GPU from AMD's website.Then,boot the system in safe mode and uninstall the previous catalyst drivers,and remove its traces from the registry as well.After that,install the latest drivers. During installation,it's better to select Custom Install instead of Express Install,and select all the components to install. This should fix the problem.
Or else,you can try to update the driver using Device Manager.