Please run the following test on the attached workbook which was created in Excel 2010:
1. Press the Help button
2. Now press it again to hide the Help. Actually, it is deleted.
3. Place the cursor in row 3, any column, and tap the down-arrow repeatedly. Everything should be normal until you reach row 11 when the background color changes. In row 13 the selection disappears. In reappears partially in row 27 and fully in row 28, with a shadow of the selection square remaining in row 27.
No such behavior can be observed while Help is visible (click the button again), nor if you restart Excel. The odd rows between 11 and 27 can be deleted to cure the problem but it will reappear after hiding the Help.
I have half a dozen sheets, all with the same problem, but it appears in different rows and seems to affect fewer rows, where the cursor disappears, when the Help is bigger. I am at a loss at how to deal with this problem. Any ideas?