Excel 2010 Table auto expand/formula copy not working

Solution 1:

This generally happens to me when formula is not the same in all cells of a column. It should be fixed if you overwrite your formula in the column and select "overwrite all cells in this column with this formula" from context menu.

Solution 2:

So it seems as though the main reason for the forumlae not being copied down is as stated above; the table was not auto-expanding when new rows were added unless they were created by dragging down and duplicating the rows above.

The formulae being copied down were variations on the same VLOOKUP, and the lookup value used in these formulae was in the column being edited when creating a new row (typed or pasted into). There appears to have been some sort of problem with the formatting in that column which caused the table to not expand as it was deciding that the new row was not intended to be in the table. Once i made sure the formatting of this column was correct, everything started working correctly.