To delete emails in the e-inbox folder or to empty folders, open swisscows.email and do the following:
1. Open your @swisscows.email account and click on "Mail".
2. Click on "Select" under "Selection". After that, a box will appear in front of each email, which is also convenient for further email editing.
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Email selection option with box in front of it:
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To completely delete content in any folder, select the folder and then select "Empty" under "ThreePoint Menu".
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After that you will be asked again, "Do you really want to delete all messages in this folder?" and with "Delete" the folder will be emptied (contents irrevocably deleted).
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