When you create a filter you get the option for automatically oe after sending. Then there is manually manually is the only time you actually get to specify a location the filter is to be applied to.

Run selected filers on Is a setting that applies to what you are manually doing, and has nothing to do with the actual filters. Just like a setting saying use broom in kitchen and then next you change it to use broom on bedroom. It does not change how Broom works and if you edit broom it is still a broom.

For a filter to work automatically on the sent folder, it must be set to "on sending". Other filters apply only on receiving new mail.

This doesn't make sense to me. I will try to explain this again In two separate filters, If one filter is "Apply filter when - After sending (check box)" it should filter the run selected filters on SENT folder of addressee A after the message is sent to move this message to folder X. Another filter marked as "Apply filter when - Getting New Mail" (check box) should filter the run selected filters on the INBOX folder to move message of the same addressee A also to folder X. What happens is If you apply the first filter on SENT folder and when you apply the second filter on the INBOX folder, it changes the SENT folder to INBOX on the first filter. This should have nothing to do with manually run filters when the box is unchecked. It seems to me that a major software revision is in order.

We probably can't understanding your problem because we can't reproduce it. A filter works on INBOX or SENT on that account were it is created. I move all my sent to a folder in Local Folders (set in account-settings)

A filter set up in Local Folders moves sent-mail to a specific addressee into another folder in Local Folders. A filter set up in a account moves mail from this addressee into the same folder.

Doesn't change anything.

OK. I guess I never will understand it.