This year (July 2016) Microsoft decided to heighten it's security features and block files that are downloaded from the internet or another computer by default. With regular files like a .xlsx or .pptx there is a prompt that notifies you the file is currently being blocked. Unfortunately, Microsoft was not kind enough to do the same thing with add-in files (.xlam or .ppam). Hence, leaving a TON of users scratching their heads as to why add-ins keep disappearing from their ribbon.
If you have recently downloaded an add-in file from this site or any other, you will want to follow one of the laid out solutions described below.
If you are a video person, Jon Acampora (ExcelCampus.com) created a great little video that explains what I will be writing in this article.
Please note that the following steps are based on using the Excel Application. Other Microsoft applications may have slightly different steps to get to the end result.
Option 1: Make Parent Folder A Trusted Folder
This option is most preferred as any file saved into a trusted folder will be unblocked without changing each individual file's properties.
- Copy your folder path (ie Ctrl +C)
- Go To File > Options
- Select Trust Center > Trust Center Settings
- Go to Trusted Locations and select Add New Location
- Paste in your folder path (ie Ctrl + V) and click OK (3 times to close out of all the dialog boxes)
Option 2: Check Unblock Property*
- Right-click the add-in file
- Click Properties
- Check Unblock
- Click OK
*This option is not preferred because if an updated file is sent to you, you will have to remember to repeat the steps to unblock the file.