This is probably simple but my brain is on strike today.

I have some data in column a in the format
yyyxxx
xxxyyy:123456abc
aaabbb:112345yku
aaccdd


What I would like to do is for each cell that has a : in it copy the
data to the right of the : to column b and delete the : in column a.

It should be simple...

I have just done a stocktake using a bar code reader and some of the
barcodes have the serial number separated from the item code by the :.
Where parts do not have a serial number there is no :.