There isn't one that is universal to the entire OS like with Mac OS X, only specific programs like Microsoft Word or Mozilla Firefox have spellchecks. In a lot of cases, with Microsoft programs at least, programs depend on having Microsoft Office installed in order for the spellcheck to function, since they just use the MS Office spellcheck program.
I know this sounds like a dumb question but how do you turn on spell check for Windows 7????

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