• Delete the file "C:\Program Files\TeamContacts\TCHelper.exe";
• In Outlook ® choose "Tools" --> "Options" --> "Other" --> "Advanced" --> "Com add-ins";
• You see a list with installed com add-ins, select "TeamContacts" and delete it;
• Now you can delete the "C:\Program files\TeamContacts" directory and run the uninstaller in Windows: "Control panel" --> "Add/remove programs".

"I started with the uninstaller in the control panel, and removed some things manually, but I still see the buttons.."

• To remove any button from Outlook ®, right-click on it;
• Choose "Customize";
• Right-click, on the button you want removed, again;
• Choose "Delete".