If you’re using Microsoft Outlook 2013 for an e-mail account that uses IMAP, you might encounter this error message when trying to delete messages from your inbox:
The message is annoying and inscrutable, but the good news is that it’s easy to fix. In Outlook, click the File tab on top, click the Account Settings button, then choose Account Settings from the drop-down menu.
In the Account Settings dialog, double-click your account name (your account name might be your e-mail address), then in the Change Account dialog that comes up, click More Settings, at the bottom. This brings up a dialog with three tabs on top. Click the Advanced tab.
In the middle, in the box for Root folder path, type “inbox”.
Click OK, then click Next. After Outlook tests your connection, click Close. Click Finish, then click Close in the main Account Settings dialog. Now you should be able to delete messages normally.