What does ALT+F+C+N do, and how to undo it?

Solution 1:

In Excel, when you hold ALT it will show the shortcut hotkeys. If you follow the trail it looks like ALT+F+C+N goes as follows:

ALT > F selects 'File' > C select 'Close' > N selects 'No' at the save prompt

So its a shortcut to close out of Excel without saving, so whatever you didn't have saved at the time is unlikely to be recovered :( Sorry man, there are tons of jerks on the internet

There is however, an AutoRecover feature in Excel 2010, if enabled I believe the default location is something like C:\Users\USERNAME\AppData\Roaming\Microsoft\Excel\

There could be incremental backups in there, depending on your settings / version!

Solution 2:

Sorry that happened to you. Sometimes the internet can be a jerk.

Just an idea about your original Excel problem, if you still haven't gotten it figured. If you change the references in your original formula to absolute references from relative references then copy it, that should do the trick.

If you don't know what absolute and relative references are, just put dollar signs ($) in front of your cell address and it will not change when you copy the formula. For example, if you have a formula like =A1 and then copy it two cells to the right (into cell C1) it will change to =C1. If you enter it as =$A$1 then copy that cell anywhere in the sheet, it will remain =$A$1.

If you need further information look for some Excel tutorials on the web. I recommend chandoo.org. The guy that runs the site is really well informed and a good teacher. I send my colleagues there all the time.