I have recently moved from Outlook to Thunderbird as Outlook developed a problem communicating with my Virgin Media email accounts. I am slowly finding my way around Thunderbird, but am experiencing a problem with some of my sub folders. This only applies to Virgin Media accounts. I have looked at previous questions on a similar topic and have tried the simpler solutions (the ones applying to advanced users are Greek to me)! Unfortunately, they haven't solved my problem. If I go to account settings and uncheck the "show only subscribed folders" box, the greyed out sub folder disappear. However, right-clicking on the folder heading and selecting subscribe and attempting to subscribe to the folders there, doesn't work. Is there a simple process I can go through to access these sub folders?