VBA seems to disappear after I protect a range of cells

VBA seems to disappear after I protect a range of cells

Hi I can't seem to get my head around this problem:
After I lock a range of cells A1:U1 (and all other cells are unlocked) and
I then protect the worksheet - the VBA in the worksheet doesn't appear to
work anymore - is there any way around this??
Thanks, Kieran