Carolyn describes a situation in which a coworker has a worksheet with large amounts of text in several cells. A few cells will not display all the text even with text wrapping and a smaller font selected.
It sounds as if this workbook is being displayed in Compatibility mode, meaning that it is in the older file formats supported by Excel. In versions of Excel before Excel 2007 there was a problem displaying everything that may be entered in a cell. While Excel allowed you to enter up to 32,767 characters in each cell, it would only display the first 1,024 characters of what was in the cell. In other words, if there is anything more than this in a cell (which could be likely in some circumstances), then it won’t display; Excel pretended like it wasn’t even there.
The easiest way to get around this problem is to save the workbook in Excel’s native format, either XLSX or XLSM (depending on whether you have macros in the workbook or not). Save it in the desired format and reopen the workbook, and you should have no problem seeing everything in the cells.
The caveat here, of course, is that if you want to give the workbook to someone else who is using an older version of Excel, they won’t be able to see all the text in the cells. In that case you might look at dividing up what is in the cells so there is less than about 1,000 characters in each cell.