Security?

Hi, I get this recently:
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Security Warning

Parsed array keys can not contain illegal characters! Script execution has been halted.

It may be possible to fix this error by deleting your browsers cookies and refresh this page.
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I do what it says and get it back. What I am doing to institute it is looking at my PHP shopping cart site. I host and do all operations, but I’m not sure where this culprit is, other than both WP and CubeCart are using the same mySQL service. Both different bases though. Since I lost my cart only two weeks ago and had to redo everything it would be neat if I didn’t have to go through it again.

Thanks in advance for any ideas, Craig