What is C2Backupfolder folder used for by CodeTwo Outlook Sync
C2Backupfolder appears in Microsoft Outlook.
On installing CodeTwo Outlook Sync in your Microsoft Outlook, C2Backupfolder folder is added to the Personal Mailbox. This folder will be used as a dumpster - a folder that retains all items and folders that are dropped/removed from the current computer due to the synchronization with the remote computer, where the items/folders were deleted. If you are sure the items and folders in C2Backupfolder will not be needed any more it is safe to remove the content of this folder. You will not damage the program either if you delete C2Backupfolder completely.
Because C2Backupfolder is a normal folder (it has no properties of the Deleted Items folder) the items and folders that are inside it will remain visible in some views of Outlook. For example, tasks will be visible in the To-Do-List, and calendar folders will be visible when you are using the Calendar View. In order to see the actual folders and items, you need to switch to the Folder List View in Microsoft Outlook or empty the C2Backupfolder.