Hi there! I can definitely help you with that.

To remove the #N/A error in Excel when using VLOOKUP, you can use the IFERROR function. This function allows you to specify what value you want to display if the VLOOKUP returns an error. In your case, you want to display a zero instead of the #N/A error.

Here's how to use the IFERROR function with VLOOKUP:

1. Start by typing your VLOOKUP formula as you normally would. For example:
   Formula:

   =VLOOKUP(A2,Sheet2!A:B,2,FALSE) 

2. Wrap the VLOOKUP formula with the IFERROR function. The syntax for IFERROR is:
   Formula:

   =IFERROR(value, value_if_error) 

   . In this case, the value is your VLOOKUP formula, and the value_if_error is the value you want to display if the VLOOKUP returns an error. For example:
   Formula:

   =IFERROR(VLOOKUP(A2,Sheet2!A:B,2,FALSE),0) 

3. Press Enter to complete the formula. Now, if the VLOOKUP returns an error, the formula will display a zero instead of the #N/A error.
   
4. You can now use this formula to sum the data you're collecting using the VLOOKUP. For example, if you want to sum the values in column B that are returned by the VLOOKUP, you can use the SUM function like this:
   Formula:

   =SUM(IFERROR(VLOOKUP(A2:A10,Sheet2!A:B,2,FALSE),0)) 


That's it! The IFERROR function is a handy tool to use with VLOOKUP when you want to display a specific value instead of an error.