Typically, you only need to activate these add-ins to use them.ĭownloadable add-ins Additional add-ins for Excel can be downloaded and installed from Downloads at .Ĭustom add-ins Developers and solution providers usually design custom Component Object Model (COM) add-ins, automation add-ins, VBA add-ins, and XLL add-ins. Some Excel add-ins, such as Solver and the Analysis ToolPak, may be available after you install Excel or Microsoft Office. Most add-ins can be categorized into three different types:Įxcel add-ins These typically include Excel add-in (.xlam), Excel 97-2003 add-in (.xla), or DLL add-in (.xll) files or they are automation add-ins. These add-ins must also be installed to use them. These can be Component Object Model (COM) add-ins, Visual Basic for Applications (VBA) add-ins, and DLL add-ins. Finally, there are add-ins that are created by third parties, such as a programmer in your organization or a software solution provider. Other add-ins are available from the Download Center and must first be downloaded and installed. Some add-ins are built in to Excel, such as Solver and the Analysis ToolPak.