Well, quite a task for an absolute beginner, but here you go:

In Workbook 1, create an additional column to check your condition. This column can be on a seperate worksheet, if you like.

A is your single column of workbook 1. B is your condition-check column.

```
B1=MATCH(A1,[Workbook2.xlsm]Sheet1!C:C,0)
```

Not sure, if I understood you right, but if you have to do this check with two related columns:

```
B1=AND(MATCH(A1,[Workbook2.xlsm]Sheet1!C:C,0),MATCH(A1,[Workbook2.xlsm]Sheet1!D:D,0))
```

Then you need to setup conditional formatting for column A of Workbook 1 to create the dynamic highlighting.

Select the whole column A, then add an conditional format based on a formula. The formula you can use is `=B1`

. When you lookup this conditional format the range which it is used on should be `$A:$A`

.

That should be it.