The Analysis ToolPak is an Excel add-in program for in-depth data analysis that is available when you install Office or Excel. To use it in Excel, however, you need to load it first.
To use Solver, an Excel add-in program, you must first load it. Solver finds the optimal value for one cell based on values in other cells.
See what to do when you get a Data Execution Protection (DEP) message about an add-in you use.
Add-ins provide optional commands and features for Excel. You must first install and (in some cases) activate these add-ins so that you can use them.