I have several cells that appear to be empty. If I run the below formula on
them, some will return blank (which is what I want them to do, but others
return #Value!
It appears to be the O column, as if I take the vale from an empty "O" that
is OK, and then paste it in to a broken "O", then it returns a blank.

How can I correct this?
Do I need to correct the data? If so, how? or do I rewrite the formula to
"trap" the error? I have another formual that works against this cell, and
if the error is here, I then get a error in the other formula.

=IF(ISBLANK(O4),"",O4+TIME(G4,0,0))


Thanks
Phil