If you cannot find the add-in that you want to enable in the Add-Ins available box, you may need to download and install it.
In the Add-Ins available box, select the check box next to the add-in that you want to enable, and then click OK.In the Manage box, click Excel Add-ins, and then click Go.Open Excel, click the File tab, click Options, and then click the Add-Ins category.It is also important to note that Add-ins may not be compatible with online or mobile versions of Excel. This solution applies to Excel 2016, 2013, 2010, and 2007 for Windows systems, and Excel 2016 for Mac.
