how do I get my email to download to my local folder inbox and empty my web based email at the same time?

Mail
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Downloading emails from email to local folder inbox

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Hi Gavin, you can use the automatic archiving in Tools > Settings > Mail > Automatic archiving, and setup a time period when your emails will empty the inbox and move it into a local folder.
Or you can setup a rule in Tools > Rules.

Hope this helps,
Paul.