|re: I don't know if you can add a vlookup to a cell that already has data|
You can't have a formula in a cell that contains hard coded data. It's one or the other: A formula or hard coded data.
In the spreadsheet I downloaded, there appears to be an issue with the values in Sheet2!C:C. The are left justified, which typically means that Excel is not seeing them as numbers but as some type of text string. That means that they do not match the values in Sheet1!B:B, even if they look the same.
You can prove that to yourself this way:
Sheet1!B409 contains 1004858
Sheet2!C21 contains 1004858
Therefore this formula should return TRUE, but instead it returns FALSE.
Now, if you double click in Sheet2!C21 and then click out of it, the value will become right justified and the result of the formula above will change to TRUE. That is because the editing action you performed in the cell caused Excel to re-format the value to be a number.
I've seen this happen in Excel many times before when data is imported from external sources. It's a pain, but it happens.
You can fix this as follows:
Select any empty cell
Press Ctrl-C to copy it
Select all of the values in Sheet2!C:C
Right-Click or click the Edit menu
In the Operations section, click the radial button next to Add
This will force Excel to Add "zero" to the values and turn them into numbers.
Now you can try your VLOOKUP formulas to find matches.
If you are still having problems with VLOOKUP after performing the steps above, come on back and we'll see what other help we can offer.
BTW...if all you want to do is highlight matching values, you can use Conditional Formatting.
See response 3 & 4 in this thread:
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