A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Had the same problem and only on one spreadsheet. I started by inserting lines above and trying the autofill. I'd skip about 100 lines at a time until I found where it started working. Then started to narrow it down and finally found the line where above it worked and below it didn't. I tried retyping the line then deleting the bad line -- did not fix it. I tried reformatting the line but still no go. Finally found that the retyped line worked but I had to leave the bad line in, but with no entries.