If you are having problems sending and receiving emails in Outlook 2003, some troubleshooting steps you can take include:
1. Check that you are connected to the internet: Make sure that your computer is connected to the internet, and that your network connection is running correctly.
2. Check your email settings: Check that your settings are correct for your email account, including the incoming and outgoing server, username and password.
3. Check your firewall settings: Make sure that your firewall is not blocking Outlook from sending and receiving emails.
4. Check your antivirus settings: Make sure that your antivirus software is not blocking Outlook from sending and receiving emails.
5. Check for updates: Make sure that you are running the latest version of Outlook, and that all of the necessary updates have been installed.
6. Repair Outlook: If none of the above steps have solved the issue, try repairing Outlook. To do this, open Outlook and go to the ‘Help’ menu. Select ‘Detect and Repair’. This will scan Outlook for any problems and attempt to fix them. However, you can try out the Regain Outlook PST recovery software.
https://www.regainsoftware.com/outlook-pst-recovery.html