Usually you do not want to do this. Note also that after August, this does not work for un-official CPCUG.org email accounts.

However if you are using desktop software to offload or archive your webmail, there are two ways. This procedure is needed if you are using POP3 instead of IMAP for offloading. See also Offloading CPCUG.org emails stored online.

Note that your Webmail Inbox.Drafts and Inbox.Sent are separate folders from your Inbox, corresponding to Drafts and Sent folders in
desktop software.

First, you might want to empty your inbox to avoid ambiguity.

Second, click on the folder whose contents you want to move. The click point is the folder name in the left panel of the
  Webmail screen.

Third, if you have no more than 10 pages in this folder, i.e. about 100 messages, click on Show All, the blue hyperlink above the addressee list on the left of the main panel. It may take some time for the Show All to display the whole set. Wait until it is fully displayed before clicking Toggle All.
But if you have more than the recommended 100 messages you will have to move page by page, in which case click Toggle.

Fourth, You should see a check mark at the left of each listed message. Uncheck any message you do not want to move.

Fifth, indicate the "Inbox" in the drop-down list below the Toggle links, and then click the (Move) button. The messages will be moved.

Sixth, if you are moving by page-fulls described in step three, then If you've unmoved messages you do not want, click each checkbox then change the "Move Selected To" folder to Inbox.Trash, then click (Move). Then click Toggle to select the next page-full to move and repeat as needed from step 4.

Once the contents of the other folder has been moved to the inbox, logout of Webmail and you're ready to offload that Inbox full to your
desktop. Uusually you want to copy that download to another folder before repeating this offload process.