Possible causes and solutions
Missing data, and #N/A or NA() has been entered in its place
Replace #N/A with new data.
Note You can enter #N/A in those cells where data is not yet available. Formulas that refer to those cells will then return #N/A instead of attempting to calculate a value.
Using the VLOOKUP, HLOOKUP, or MATCH worksheet function to locate a value in an unsorted table
The MATCH worksheet function contains a match_type argument that specifies the order the list must be sorted in to find a match. If the function cannot find a match, try changing the match_type argument. To find an exact match, set the match_type argument to 0.
If the array formula has been entered into multiple cells, make sure the ranges referenced by the formula have the same number of rows and columns, or enter the array formula into fewer cells. For example, if the array formula has been entered into a range 15 rows high (C1:C15) and the formula refers to a range 10 rows high (A1:A10), the range C11:C15 will display #N/A. To correct this error, enter the formula into a smaller range (for example, C1:C10), or change the range to which the formula refers to the same number of rows (for example, A1:A15).
Omitting one or more required arguments from a built-in or custom worksheet function
Enter all arguments in the function.
Using a custom worksheet function that is not available
Make sure the workbook that contains the worksheet function is open and the function is working properly.
Running a macro that enters a function that returns #N/A
Make sure the arguments in the function are correct and in the correct position.