@jem101 is right. Bin means bin. VM have no way of knowing that you really think bin means storage and so the VM mail system behaves accordingly. Your practice is obviously problematic and you have discovered to your cost. Don't blame VM for that. Your idea of setting up a second folder as temporary holding area is so blindingly obvious, words fail me. But there is something else. If you use the mail archive function a separate archive folder is created in date (year) order so you can store mail until you need it again and find it easily. But there is an overall 25GB limit on the size of your mail box. Frankly if you are using VM mail for business purposes you should think again. It is not designed for that. It is not robust enough to cope with large volumes of mail.
There is no 180 item limit on the trash folder. What there is a variable deletion process. In principle stuff over 7 days old is deleted every seven days but the VM mail system does odd things at odd times.
Most of the sensible people here that I know have long since stopped using it and have chosen something better from the range of free ad supported services. They tend to be more resilient and have better spam filtering than VM. Indeed last night the whole of the VM single sign on system went down for a short while cutting off access to VM mail.
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