Messages within your webmail that have strikethroughs are likely messages that you deleted in Outlook but were not removed from webmail. The cause of this is due to how Outlook treats deleted messages - until certain triggers are initiated those messages are only marked as deleted and are not physically removed.

To start, you can force Outlook to physically delete the message by either:

1. Closing Outlook
2. Leaving the folder that contained the deleted message

Once the above step has been taken, simply refresh your webmail by clicking the circular icon in the top right of your webmail.

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