Detect errors in formulas - Microsoft Support

You can use error checking to detect errors in formulas. The rules don't guarantee error-free worksheets, but they can help find common mistakes. Errors can include: Cells containing formulas that result in an error, inconsistent calculated column formula in tables, cells containing years represented as 2 digits, numbers formatted as text or preceded by an apostrophe, formulas inconsistent with other formulas in the region, formulas which omit cells in a region, unlocked cells containing formulas, formulas referring to empty cells, and data entered in a table is invalid.

Detect errors in formulas - Microsoft Support

Detect errors in formulas - Microsoft Support

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Detect errors in formulas - Microsoft Support

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Detect errors in formulas - Microsoft Support

Detect errors in formulas - Microsoft Support