How to find duplicates from two workbooks (if duplicate add new value in the list)

Hi,

I really need help. Here is my case.
Each month I will have an "old list" and a "new list", so two separate workbooks.

"old list" has column A, B, C, D, E.
"new list" has column A, B, C, D, E, F, G. or just the "new list" has column A, B, C, D, E.

Column A is a list containing words.
Column B are value (numbers).

My two workbooks are opened. I would like to find the duplicates i(column A) in the new list from the old list and if there is a duplicate in the new list I would like that duplicate to be highlighted and the value in column B to replaced the value in "old list" column B.

For instance if "old list" A3 is Lab and in the "new list" Lab is in A2 I would like A2 in the new list to be highlighted and the value corresponding in B2 10(-1) to be paste in B3 in the "old list"

Is it confusing? I attached four excel files to visualize what I am looking for. It's easier when you look at it.

I will need to do it every month and the list has a lot of data. I am looking for a macro or a good formulas to do the work.

I appreciate any help. Many thanks.