Why does EXCEL insert bace breaks on every cell of some worksheets
 

On some old worksheets, EXCEL is setting page breaks at every cell.
Specifying a smaller group of cells as the print area restores the desired
single page, but dragging the page break over or down one more cell causes
the breaks to appear at every cell ans a message that the margin doesen't
fit.
It seems that the page size is suddenly reduced to less than 1inch x 1 inch.
Resetting the margins to .05 allows the page to be displayed, but adding a
row or column again trips back to one cellper page?