Yes, you can check your e-mail quota in Thunderbird by following the steps below. These steps are only applicable if you are using an IMAP email account. You may also check your quota online (if you are using either IMAP or POP) at http://webmail.saintmarys.edu.

To check your e-mail quota using Thunderbird:

1. Open Thunderbird (if it is not already open).
2. In the column on the left, right-click on your Inbox. (If you are using a Mac, you can press the Control key and click on the Inbox.)
3. From the menu that appears, select Properties.
4. In the Properties window, click on the Quota tab.
5. The quota tab shows you the percentage of space you have used, as well as showing the actual amount of space used. The amount used includes attachments and any mail you have in the trash that has not been deleted yet.