Tried To Install 4.3.9 But Fileinfo Php Extension Error.

Current version 4.3.3 running mostly well. Thought I would test out 4.3.9

in a separate folder and got this when I attempted to install.....

The Fileinfo PHP extension is not installed. Precise detection of types of the uploaded files will be unavailable.

If I enable fileinfo PHP will it stuff up the running of my current 4.3.3 store ?
The highest version of PHP available to me is 5.6 ( which I have running presently ).

It will not affect 4.3.3 installation. You can enable fileinfo without any worries

Thanks. Thought I could and all went well until the import