Webmail uses folders to manage your email. There are several default folders that are created (inbox, sent, drafts, trash). The user can create additional folders if needed. Each of the folders is actually a separate file on the mail server. Messages are stored one after the next in the file.
For example, if you have 10 messages in the your inbox and you want to delete message number 3 , the webmail program has to copy the messages you are going to keep (1,2,4-10) from the inbox file to a temporary file. After it finishes it replaces your inbox file with the updated temporary file and then removes the temporary file. Since each email account is allocated a fixed amount of diskspace, there must be enough space for both the inbox and the temporary file. The user will get an error when their is not enough room to create the temporary file while keeping the original file at the same time.

Suggestions

1. Always purge your trash folder. Deleting messages does not remove them, it justs moves them to the trash bin. Purging the trash bin removes them and releases disk space for new messages.
2. If you receive pictures or documents via email, download the attachments to your computer and remove the message from the server.
3. If you decide to keep a large document or attachment on the server, be sure and move the large messages/attachments to a subfolder. By keeping a message on the server, your are essentially reducing the size of the available space for other messages. For example, if your email account is 10MBs and you are keeping 6MBs of messages with attachments, then you can only receive new messages under 4MBs in size.
4. Create sub folders and move messages that you need to hold onto in these folders. Eventhough these count against your email quota, they make the inbox folder smaller. The smaller the inbox folder the greater the chance you will have enough room to create the temp files when deleting a message.

If taking these steps does not resolve the problem, then you have two choices. Your first choice is configure an email client (Outlook or Outlook Express) so that messages will be removed from the server and downloaded to your computer. Your other choice is to purchase additional diskspace allocated to your email account. Contact your sales representative for additional space.