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With autocomplete, OpenOffice has managed to make a completely useless, very annoying behavior default. They've also done a good job of hiding the menu options to disable the "feature," and have hidden it in different places in different tools. This is a case where consistency would reduce the impact of a stupid default. Anyhow, as others have mentioned, whenever I'm using a freshly-installed OpenOffice (e.g., after installing a hopefully less-buggy version of Ubuntu), OpenOffice reminds me how much I dislike this "feature." And I spend too much time hunting down how to kill it.
First, in OO Writer it's not really that well hidden. Copied from http://nowacki.org/blog/2004/05/disable_autocomplete_in_openoffice.html: * Tools -> AutoCorrect/AutoFormat… * Word Completion tab * Uncheck “Enable word completion”
Unfortunately, this doesn't disable the "feature" in OO Calc, and the OO Calc option is very well hidden. Today I really was having trouble figuring it out--it is, of course, not in what passes for help in OO--which led me to nowacki.org via Google. From their blog entry: Tools -> Cell Contents -> AutoInput
Of course, this is the root of the problem: we're supposed to magically know that in OO Calc they call it autoinput rather than autocomplete. What, if anything, are the OO folks thinking? This has been a usability problem and unnecessary time sink for a lot of people for a long time now. When will they disable it by default, or at least make it possible to find the option in OO Calc? Or maybe talk about disabling it in OO Help?