Hi Marisa,
You mean by the black arrow turns blue that the filter dropdown has a blue
triangle? This means that that filter is active. Choose Data, Filter, Show
All and your filters should be active again.

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Cheers,
Shane Devenshire
> I finished creating a huge database and had been using the Auto Filter to
> help me plug in data and analyze it. When I finished in the particular column
> I was working on, the black arrow that appears when you turn the feature on,
> had turned blue and now I can't Auto Filter anything in the entire
> spreadsheet. If you have any advice please let me know as I don't want to
> have to recreate this entire thing