OK, using Thunderbird 3.XX, I have three mail clients and use the "Unified folders" view so all mail appears in one "inbox". All was good until I changed settings on two of my mail clients by highlighting the radio button in "junk settings" and then selecting "move new junk messages to:" and radio button "other/local folders/trash". at which point I now had two trash folders in my "Unified Folders", one of which displayed sub-folders of my mail clients and local folders. Reversing the action had no affect, No matter what I tried, I could not get rid of the two trash folders! I have TB set at the default "junk settings" with "move new junk messages to:" radio button "deselected"
After several attempts to delete one of the folders, including in the root directory with no affect, I finely nailed the solution, there is apparently a "glitch" with TB 3.XX where there is a corruption of sorts with the junk and trash settings!
Here's the fix that worked for me......
After restarting TB, in one of my mail clients I went back to "Junk Settings" and now selected "Move new junk messages to:" and default radio button "Junk folder on:" and selected OK.This now put a "Junk" folder in the chain along with the two trash folders. Close TB and restart. Now go back to the same mail clients "Junk settings", deselect the "Move new junk messages to:" radio button and select OK. The junk folder and two trash folders were still visible in the chain, right click on and "delete" the junk folder, it now changed the junk folder icon to a "gray folder" icon, I right clicked on that icon again and hit delete, the folder still remained but after a restart of Thunderbird, it all returned to normal with both junk folder and the second trash folder now removed and functioning as it should.
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