Double clicking on Titlebar results in a rolled up window

When I double click on the Titlebar, I don't get the expected maximized window. Instead, it shrinks and appears rolled up as shown in the picture below. Double clicking returns to original size window, I can also drag the corner to resize this "shrunken window. Is there anything I can do to stop this action? I am using Vista, but it also happened in XP Pro.

Try: Settings/Preferences/Listers/Options/Zoom Lister when title bar is double clicked.

Lou
Hard work never killed anyone, but why take a chance?

[quote="lou"]Try: Settings/Preferences/Listers/Options/Zoom Lister when title bar is double clicked.
[/quote]

That did it, Lou! Thank you very much!

Randy