If you’ve used the Mailbox Cleanup tool to look at the size of your Outlook folders, you might have noticed three (or sometimes four) folders starting with “Sync Issues.” You can empty the “Sync Issues\Conflicts” folder with the Mailbox Cleanup tool, but that still leaves the others. Let’s take a look at how to access them, what they’re for, and whether you can—or should—delete their contents.
How Do You Access the Sync Folders?
If you’ve never used it before, check out our guide to using the Mailbox Cleanup tool. Its View Mailbox Size feature shows you the size of all of the folders in Outlook. Scroll down towards the bottom of the list to find the Sync Issues folders.
You won’t see these folders by default in the navigation pane in Outlook, so we’ll start by making them visible. At the bottom of the navigation pane click on the ellipsis (the three dots) and select the “Folders” option.
This changes the view in the Navigation pane to show all of the mail folders in your mailbox, including the Sync Issues folder and its three sub-folders.
Messages in the Sync folders are only visible within the Outlook client on your machine, so you won’t find them in the Outlook web app.
Read more: https://www.howtogeek.com/377695/view-and-delete-sync-issues-in-outlook/