Everyone loves the side-by-side windows feature of Windows 7, where you can dock windows to the sides of your monitor by dragging them (or pressing ÿ+? or ÿ+?). But sometimes it doesn’t appear to work if you have several documents open, and want to compare them side by side, particularly if they are spreadsheets.
It’s all to do with how applications open multiple windows. Microsoft Word, for example, opens each document in a separate instance of Word, so if you have two docs open, it’s a snap to show them side/side. Excel, by contrast, prefers to open each new worksheet within a single “Excel” application.
So, whilst Windows 7 will show previews of multiple windows, they’re actually just multiple documents opened within Excel.
If you want to see Excel windows side by side, try going into the View menu in Excel, and click on the View Side by Side option on the Ribbon, then choose which of the additional open worksheets you’d like to compare the current one with.
There’s also the option in Excel to “tile” open worksheet windows, so you could have more than 2 arranged side by side or one above the other.