I have two buttons, Evernote and Open Boomerang in the Mail section of the Outook 2013.
I am unable to get rid of them because they are not listed in the Add-ins option nor in manage COM add-ins.
I don't understand how outlook is not able to know/show the add-ins installed on it.
This was a head scratcher, and the only way I figured it out is when I noticed that the Boomerang and Evernote icons were only shown in Outlook 2016 when I was looking at an Outlook.com (for me, Hotmail.com) email address. When I looked at my hosted Exchange email account or various IMAP accounts, the Evernote and Boomerang icons disappeared from Outlook 2016. Which leads to the answer! These things are NOT installed on your computer or in Outlook 2016, so you can't get rid of them that way. Instead, do the following:
This is pretty obnoxious. The add-ins dialogue reports that I installed these items, but that isn't true. I have no idea how they got turned on as I never use the web interface.
These look like Office Store add-ins. In Outlook, go to FILE -> Manage Add-ins.
Click the Get Add-ins icon on the ribbon and remove the apps. these apps got installed via this "Get-Add-ins"
Right click on the boomerang icon, select "customize the Ribbon", then in the right side of the window that opens look into "add in" located under the "Main tabs" and then "Home" drop down menu. Click on boomerang and select "remove", same for evernote. It took me a while to figure too.
Click the store icon, click My add-ins, select Evernote (or other undesired add-in) and click Remove/Delete.
For me, on Outlook 2013, the Evernote add-in showed up only when my Outlook.com account was selected. It did not appear when viewing my Gmail account. The option to manage add-ins was not on OWA.
