I am tryinr to upload a reasonably sized image and am getting this message:

xxxx.jpg: Exceeds your quota by 65.4 KB. <a rel="nofollow" href="misc.php?do=attachments" target="_blank">Click here to view your attachments</a>

Is there a limit of total size of all attachments?

If so, what do I have to do to increase it?

I have gone to the Attachment Manager and can't seem to find a way to remove any of the ones I have already uploaded