Can anyone explain how I could replace all the semi-colon's in a column with
the equivalent of an alt+enter so that each value will appear on one line
within the cell?

I have a list of names that are separated by ; and I want to have each name
on a separate line in the cell, without creating a new cell or row. So I
start out with

Smith, J;Smithe, C;Smythe, E

and I want to end up with:

Smith, J
Smither, C
Smythe, E

I would need to do this for all the cells in a particular column so if there
is a way to repeat it that would be great. Each cell has a different number
of names so I'd like something that looks in each cell in the column for a ;
and replaces it with a alt+enter and moves on to the next cell to perform the
same task.

It seems like a simple task but it's driving me crazy, I'm doing it manually
and I know there's a better way.

PS, the simpler the better, I don't know a lot about Macros and such.

Thank you.