I have a large spreadsheet in Excel 2010 with multiple worksheets. This morning I edited a formula in one of the cells of a table then tried to copy it to the other cells in the column using ctrl-c and ctrl-v, but Excel would not copy the revised formula into the other cells. I tried using the mouse to copy and paste and tried copy and paste formulas only, with no luck. I tried copying to just one cell, but it would not do it. I did not get an error message or anything. I can manually edit the formulas in the other cells, but there are almost 13,000 lines on this worksheet, so that is was not a practical way around this issue. I rebooted my computer and even tried doing the copy and paste on a different computer, still no luck. I finally inserted a new column into the table, highlighted the text of the formula and pasted it into the new column and Excel copied it down into the other cells with no problem. I am totally baffled as to what was going on in that original column. Any ideas?