AppleShare IP 6.3: A User Is Having Trouble Sending Mail
This article provides troubleshooting information for AppleShare IP 6.3.
If the mail is addressed to a user who connects to the same mail server, verify that mail is enabled for the addressee.
Make sure that the user's e-mail application is properly configured for your network with the correct mail server name, e-mail address, and so on.
Check the Mail Server Activity window. If the number of active users and the number of users sending mail is always high, there may be too many users trying to connect at the same time. Try allocating more memory to mail services.
Make sure that there is enough free space on the volume where the mail database is located.
Check the size of the mail the user is trying to send; the mail server may limit the size of messages. You can change incoming mail restrictions to allow larger messages to your server.
Check the mail server log to see if there is a pattern of failed connections for the mail server.
If the destination is a computer for which you provide DNS service, check the MX record on the DNS server. If you change the MX record, remember that DNS caches must be flushed before the change takes effect.
Make sure SMTP mail is enabled on your server. The default SMTP port is 25. See Changing mail protocol settings.
Make sure that the mail server and the user's computer are using the same DNS server. (The DNS server is specified in the TCP/IP control panel.) If they are using different DNS servers, make sure the MX records match on both DNS servers.