Sidebar Widgets Not working–WARNING: array_key_exists()

Please Help!

I am receiving the error code:
Warning:array_key_exists()[function.array-key-exists]:The second argument should either be an array or an object in /home/thename/public_html/thesite.com/wp-includes/widgets.php on line 858

I can no longer do ANYTHING with the widgets section of the admin panel!

I can’t drag and drop anything to replace the widgets…I don’t even want widgets anymore!

This all started when I tried to remove a widget that wasn’t working properly.

And YES, I had deactivated all the plugins to detect what is causing this, but the problem persists…

I’m no coding expert, but after going to Google to find solutions for this apparently this is quite common as of late across many different themes—so it’s not just a one particluar theme problem!!

I found HUNDREDS of sites with the same warning error message in the same line….what’s the deal and how do I fix it….seems as if it should be a “simple” fix.(?)

Advice would be greatly appreciated…..

I upgraded hoping this may help resolve the issue…but it seems as if every two week when there is a new WP update, there are a whole new set of problems that arise.

EVERYTIME I’m at the end of almost completing a WP project there’s always some other type of bug issue that arises:(

Please HELP!! Oh—and please respond to me like an 8 yr old—I know some of you are way advanced, but everyone isn’t:)

Thanks…