You can tell right away that an Excel 2019 formula has gone haywire because instead of a nice calculated value, you get a strange, incomprehensible message. This weirdness, in the parlance of Excel 2019 spreadsheets, is an error value. Its purpose is to let you know that some element — either in the formula itself or in a cell referred to by the formula — is preventing Excel from returning the anticipated calculated value.
The following table lists some Excel 2019 error values and their most common causes.
| What Shows Up in the Cell | What’s Going On Here? |
| #DIV/0! | Appears when the formula calls for division by a cell that either contains the value 0 or, as is more often the case, is empty. Division by zero is a no-no in mathematics. |
| #NAME? | Appears when the formula refers to a range name that doesn’t exist in the worksheet. This error value appears when you type the wrong range name or fail to enclose in quotation marks some text used in the formula, causing Excel to think that the text refers to a range name. |
| #NULL! | Appears most often when you insert a space (where you should have used a comma) to separate cell references used as arguments for functions. |
| #NUM! | Appears when Excel encounters a problem with a number in the formula, such as the wrong type of argument in an Excel function or a calculation that produces a number too large or too small to be represented in the worksheet. |
| #REF! | Appears when Excel encounters an invalid cell reference, such as when you delete a cell referred to in a formula or paste cells over the cells referred to in a formula. |
| #VALUE! | Appears when you use the wrong type of argument or operator in a function, or when you call for a mathematical operation that refers to cells that contain text entries. |
