Follow these instructions to select multiple emails in webmail interface on Windows platform and IPSwitch Imail Server:

1. Select multiple emails using Shift Key and Mouse Click.  Click on top first email and then keep Shift key pressed and click on the last email.  You will see all emails listed in between first and last are selected.  If you keep pressed Ctrl key and click any email within selected emails, you will see that email has been un-selected keeping all other selected.
   
   
2. Keep Ctrl key pressed and clcik with mouse one by one emails to have all clicked emails selected.
   
   
3. In some browsers, you can select multiple emails with mouse only by keep mouse clicked on starting email and drag mouse cursor to the last email.

Once emails have been selected, now you can right-click with mouse and delete emails or marked them Unread/Read.  You can also use menu bar icons to apply action on all selected emails.