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Folders will not load sometimes when you click on them. For example, I am in Sent. I click on Inbox and the column that shows everything in the box (middle pane that displays the list of e-mails) is blank. I find the only way to solve this is click on another folder and then jump back to the one I want or refreshing the page. I'm not sure if this is related to the general slowness of smartermail or a failure to load issue.