corroded batteries have brought my wireless keyboard to a halt. I have cleaned everything but too no avail??

You have to clean off corrosion thoroughly. I am not saying you haven't tried but you need to pay particular attention to the terminals inside the compartment and if you have tried the new batteries and then gone back to re-clean the terminals you then need to clean the battery terminals again. Does the green light flicker, and what make of batteries are you using?

Pleases to read that; thank you for the solved star. If you want to know a little more about batteries, take a look at my user tip, here ...

https://discussions.apple.com/docs/DOC-9451