I wander if anyone can help with this.
We have an external database hosted by a 3rd Party,
This database sends emails to our internal staff via it's own smtp service and needs to send from an internal email address (spoofing)
Currently we have a Spam Appliance that blocks Spoofed emails so this is causing problems.
We have Exchange 2007
I need to find a solution to this as we now have 3 different external databases with 3 different supplier that all need to do the same and this is likely to increase.
The options I have currently got are:
1. Allow Spoofing into the company (we get way too much spam and phishing if i do this so want to avoid this option)
2. Whitelist the IP address of the SMTP service to stop any emails from being blocked (The IP's are shared with other services and companies so would be potentially allowing SPAM and Viruses should those services become compromised, etc)
3. Allow the External databases to connect directly to our internal Exchange Servers and email from these.
4. Force the database servers to email as some other domain (apparentely not an option!)
Can anyone advise me of any other options that i have missed?
Does anyone know how I could allow option 3 and ensure that everything is secure as possible?
Thank you for your help