how to delete a folder in tbird that tbird says the mail server for the email responded NONEXISTENT mail box. the email address inbox and subsequent folders do list under the @icloud.com tbird address. the folders i have deleted on my iOS device are also listed and when i try delete them, export them or even rename them the NONEXISTENT message show up from tbird. i know the folder does not exist, i deleted it and yet i cant remove all these deleted NONEXISTENT folers in tbird. this list of folders is getting very long and i have to find a way to greatly reduce this long list but, again, tbird wont let me move, delete, rename, move to trash, move to junk or move to a new folder i created called "2 DELETE". WHAT CAN I DO?