Follow the instructions below to open another mailbox that you have access to using the web interface.
Login to your own email account at email.abwe.org.
Click on your profile picture, then click on "Open another mailbox".
Type in the email address of the mailbox you have access to.
Confirm it is the email you want to open and click "Open".
The mailbox will open in a new browser tab. If it does not open, then you do not have permission to the mailbox.
Please contact firstname.lastname@example.org if you should have permission.