How can I minimize the chances of getting email rejected when I've got multiple locations?
I've got eight offices in different cities. Each one uses a different ISP. Our mail service is provided by a third party (our domain host, Network Solutions).
There are three primary causes for rejections:
1. Spammers will use NetSol and wind up getting the NetSol mail servers added to block lists. This causes my legitimate mail to be rejected simply because I have the misfortune of using the same SMTP server.
2. I think our mail looks like it's forged to some mail servers because the origin IP address (taken from the client PC) doesn't match the address of our mail server or something to that effect.
3. We can usually get around issue #1 by changing the SMTP server on the client to the one used by their respective ISP. However, at least one of our ISP's will reject outgoing mail (using their SMTP server) that doesn't use their domain in the sender's email address. I don't want our company mail going out with any domain name other than our own. The recipients have to see user@mydomain.com instead of user@someisp.com.
I've been considering installing an in-house mail server, but that still doesn't solve issues #2 and #3 for my remote offices.
Is my best option to setup an in-house mail server and configure these remote PC's to access it via a VPN connection? I don't know much about VPN's but wouldn't that make any outgoing mail look like it came from a PC in the same domain as the mail server (thereby eliminating issues #2 and #3)? When I posted another email question a while back, someone suggested using Exchange Server 2003 with RPC over HTTP. Would that be a better option?
I'd appreciate any help with this matter. I'm still pretty much a n00b when it comes to email issues.
I've got eight offices in different cities. Each one uses a different ISP. Our mail service is provided by a third party (our domain host, Network Solutions).
There are three primary causes for rejections:
1. Spammers will use NetSol and wind up getting the NetSol mail servers added to block lists. This causes my legitimate mail to be rejected simply because I have the misfortune of using the same SMTP server.
2. I think our mail looks like it's forged to some mail servers because the origin IP address (taken from the client PC) doesn't match the address of our mail server or something to that effect.
3. We can usually get around issue #1 by changing the SMTP server on the client to the one used by their respective ISP. However, at least one of our ISP's will reject outgoing mail (using their SMTP server) that doesn't use their domain in the sender's email address. I don't want our company mail going out with any domain name other than our own. The recipients have to see user@mydomain.com instead of user@someisp.com.
I've been considering installing an in-house mail server, but that still doesn't solve issues #2 and #3 for my remote offices.
Is my best option to setup an in-house mail server and configure these remote PC's to access it via a VPN connection? I don't know much about VPN's but wouldn't that make any outgoing mail look like it came from a PC in the same domain as the mail server (thereby eliminating issues #2 and #3)? When I posted another email question a while back, someone suggested using Exchange Server 2003 with RPC over HTTP. Would that be a better option?
I'd appreciate any help with this matter. I'm still pretty much a n00b when it comes to email issues.
