automatic find and replace based on a table

[saintdesy]

I have a file with thousands of part numbers which repeat thousands of times randomly throughout the file and I have a sheet with a corresponding list of part numbers which need to replace the part numbers in the original file.

For example, the first file will have the part number CLS1001, which I need to replace with the new part number C508, then CLS1002 which I will need to replace with C511, and so on. Each of these CLS numbers repeat themselves many times in the file. The second file is basically just a table which shows which of the new numbers corresponds to which of the old numbers like below:

Old Number	New Number
CLS1001	C508
CLS1002	C511

Is there any way I can use the information in this table to automatically replace every instance of the old part number with the corresponding new part number in first file?

Edit: I have to add that there are a TON of numbers to replace, not just these two, so a normal find and replace is not practical.

[K m]

Try VLOOKUP(old_number,number_array,column,False)
Where:
Number_array = the table with the old and new part numbers
Column = 2 in this case

This assumes you need to do many times. If you need to do it once REPLACE works best