Excel could really use an option (probably under "Start up Options") to automatically re-open all previously-open Excel files the next time Excel is started back up after all active Excel files are closed (whether that happens via the "Close all windows" option or system reboot, shutdown, or crash). This would be the Excel equivalent of the option of most web browsers to save all open tabs when the browser is closed and re-open them the next time it is launched. As a user who typically keeps multiple Excel files open at once, it's a huge pain in the neck to re-open all of them after a reboot (and I always worry that I'm forgetting something and losing track of a file I wasn't done with yet), and just the desire to avoid all of that can contribute to me postponing system updates because the necessary reboot is so much of a hassle. It also leads to all of my open Excel files continuously consuming system resources even when I'm not actively using them. I've even resorted in the past to trying to deliberately trigger Autorecover by crashing Excel with un-saved changes instead of properly shutting it down, because that was the closest thing I could find to this feature. And yet I believe that Excel already has the capacity for a feature like this, because I'm pretty sure I've seen it automatically re-open all of my previously open files when restarting to install Microsoft Office updates; so all you should need to do is enable to option for us to take advantage of this functionality at any time. This suggestion goes for the other components of Microsoft Office (particularly PowerPoint and Word) as well.

I wish Excel would show the cells I have selected when the window doesn't have focus. Currently, the "highlighting" that shows which cells are selected goes away when the window loses focus. I often have one or more spreadsheets open at a time (or multiple windows of the same spreadsheet), and I crosscheck data between the info in each Excel window. The absence of persistent highlighting of when focus changes drastically reduces productivity and makes the who process more difficult than it needs to be. Since some Windows apps don't do that, I suspect there is a reason why MS implemented this behavior. Would love it if you guys looked at this again to see if there's a way you can support it. Thanks!

Create a formula to handle exception cases of an expression without needing to use IF functions and restate the expression multiple times. The proposed formula would be easier to check/understand, lighter weight (especially with complex nested formulas), and less error-prone.

Suggested syntax--
UNLESS(expression, value1, result1, [value2, result2], ...)

(The function would be similar to a SWITCH, except that if no match is found, it would evaluate to the original expression instead of an error.)

In the way that--
=IF( ISERROR( SomeComplexExpression ), AlternateResult, TheSameComplexExpression )

Can be written more cleanly as--
=IFERROR( SomeComplexFunction, AlternateResult)

By analogy the functions--
=IF( SomeComplexExpression >= 15000, AlternateResult, TheSameComplexExpression )
=IF( SomeCellReference = 0, "", TheSameCellReference )

Coule be simplified to--
=UNLESS( SomeComplexExpression, ">=15000", TheSameComplexExpression )
=UNLESS( SomeCellReference, 0, "" )

The problem of the CF Rules Manager getting convoluted and very difficult to manage (as a result of copy and paste of cells) is well known and documented elsewhere. I have seen spreadsheets where a single Conditional Formatting rule has been duplicated for individual cells 100's of times. I have a partial workaround to prevent the Rules Table turning into a mess which is described in the attached file.

This is a blunt-force solution
Essentially apply your CF to large range - possibly $A:$XFD - which is every cell in your worksheet, then use formulae to identify which cells to apply the CF to. I showed 3 different approaches that use this method, they all work and, I think that it is probably about the only non-VBA way of using CF in a reliable way. Hope it's useful to someone out there.

The problem of the CF Rules Manager getting convoluted and very difficult to manage (as a result of copy and paste of cells) is well known and documented elsewhere. I have seen spreadsheets where a single Conditional Formatting rule has been duplicated for individual cells 100's of times. I have a partial workaround to prevent the Rules Table turning into a mess which is described in the attached file.

This is a blunt-force solution
Essentially apply your CF to large range - possibly $A:$XFD - which is every cell in your worksheet, then use formulae to identify which cells to apply the CF to. I showed 3 different approaches that use this method, they all work and, I think that it is probably about the only non-VBA way of using CF in a reliable way. Hope it's useful to someone out there.