I have installed OS X Mountain LION on my MacBook Pro 13" and cannot open anymore Microsoft Word or Excel ? Could you help me with this problem? Thank you.
Why suggest "ignore iWork"? I use iWork exclusively now, since dumping MS Office and I like it.
On its own it's fine, as a replacement for Office it's mediocre. Unable to save in Office format you are pushed into exporting (extra steps) simply to create an Office compatible file. Pages barely renders a Word document correctly (a trait also shared by Libre/Open Office). Numbers is a very poor substitute for Excel (the free ones are better).
And for all this you are expected to pay, whereas the other alternatives do a better job (with MS Office files) without a financial insult.
If Office is not in the equation I recommend iWork.