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.
Right-click on Microsoft Office 2007 and click Change; Click on Repair and then click Continue; After Microsoft Office 2007 finish repair, you need to restart your Windows. Run Microsoft Word 2007 or Microsoft Excel 2007. Method 2: Change permission for registry keys. If the first method did not solve your problem, try this method. Disabling these add-ins may fix the issue of an Excel file opening as a blank workbook. Open Microsoft Excel. In the Ribbon, click the File tab and click Options in the left navigation pane. Click Add-ins on the left side of the Options window. In the Manage drop-down list at the bottom, select COM Add-ins and click Go. Subscribe Now:More:Microsoft Word disappears, you can res. Yes, Windows 10 may remove your programs without asking you–but you can get them back pretty easily. This is the takeaway from some people’s experiences with the “November update,” Windows 10’s first big update. Microsoft has refused to comment on this, but it seems like the update process is designed to remove incompatible programs.
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
Excel Disappeared From After Microsoft Office Update Error Code 0xc0000142
Excel Disappeared From After Microsoft Office Update Error
*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.
Excel Disappeared From After Microsoft Office Update Not Working
Hopefully, this solution gets your add-ins staying in place! In case this did not solve your issue, here are a couple more articles on the topic that may be of help: