Re: SMTP service queue slow
Does the delay happen on internal email delivery ? Make sure that your antivirus or firewall is not running in server, because it may result in delay. restart the SMTP services and send mails in limited way . Restart SMTP services and make sure you send out 50 mails and not 500, it happens that your server IP might get black listed for Spaming and might get into blacklisted IP address.
Re: SMTP service queue slow
What you can do is open exchange system Manager and expand Servers- Server name - Protocols - SMTP- right-click "Default SMTP Virtual Server" and click Properties. in general tab General tab check "Enable Logging".now go to Extended Properties, and select enable All the logging Options. Click OK to apply the modification. after doing that Right-click Default SMTP Virtual Server and click Stop. Right-click Default SMTP Virtual Server and click Start to restart the SMTP server.