here is what I"m looking for. I don't know if it needs to be a macro.
Thanks for taking a look:

If text in column B does not contain any text that contains NYSE:,
NasdaqNM:, NasdaqSC:, Amex:, then find text in column G that does contain
NYSE:, NasdaqNM:, NasdaqSC:, Amex: and return that entire phrase of text to
column b.

here is the data set:
Column A Column B ... Column G
Nokia HLSE:NOK1V HLSE:NOK1V, BMV:NOK.N, ENXTAM:NOKA, NYSE:NOK

The cell in Column G has a lot more text than showed here.

Then I would like the data in Column B replaced with NYSE:NOK.

When I say Column, I am referring to a particular cell in the Column. This
worksheet has about 2000 rows of cells in each column.

Thanks for your help!