Add-ins are programs that add optional commands and features to Microsoft Excel.

Most used Excel Add-ins

Installing add-ins on your computer : Before you can use an add-in, you must first install it on your computer and then load it into Excel. Add-ins (*.xla files) are installed by default in one of the following places:

• The Library folder or one of its subfolders in the Microsoft Office/Office folder.

• The Documents and Settings/<user name>/Application Data/Microsoft/AddIns folder.

The administrator for your company's network can designate other locations for add-in programs.

Loading add-ins into Excel : After installing an add-in, you must load it into Excel. Loading an add-in makes the feature available in Excel and adds any associated commands to the appropriate menus.

Unloading add-ins from Excel : To conserve memory and improve performance, unload add-ins you don't use often. Unloading an add-in removes its features and commands from Excel, but the add-in program remains on your computer so you can easily reload it. When you unload an add-in program, it remains in memory until you restart Excel.