> I have a dynamic IP from my ISP which means I don't want to send my own email, as some people consider mail from dynamic
> automatically spam.
Anybody using the Spamhaus-ZEN blacklist will reject mail from dynamically assigned IP addresses. Many other blacklists also use this technique.
> Furthermore my ISP restricts the number of unique FROM: email addresses when sending to 10 and I have to register all email addresses that will
> be used for sending. I run a small business and this limitation of max of 10 outgoing addresses is hurting me.
How about getting a fixed IP address. Is the cost that much more than the dynamically assigned IP address.
>
> I see two solutions: 1) is to pay for a SMTP service to relay the mail for me. I've done that in the past, and it's ok, but they're
> expensive.
I'm not all that sure it's all that expensive. DynDNS costs ~$15/year for 150 relays and you can buy this in blocks to increase the limit.
https://www.dyndns.com/services/sendlabs/outbound.html
> 2) my ISP (Rogers in Canada, which is in cahoots with Yahoo by the way) allows multiple mail boxes, so I've been thinking that I set up
> a mail box for each employee. But this means that the Mercury Relay SMTP client somehow has to send to the correct Rogers/Yahoo mailbox
> depending on which of my employees is doing to the sending. And I don't think it can do that.
The employees could bypass Mercury when sending and send directly the the Yahoo host.
> So then plan B was to run multiple Mercury's - one for each employee.
A real pain in the rear!
> But this becomes a nightmare to administer, and I've been running Mercury forever (10 years+) and how do Itake the various user
> sections apart into separate folders for each mercury?
> So do you have any suggestions on how I can solve this?
1. Get a fixed IP address.
2. Talk to your ISP and tell them you are running a business and the outbound limit in killing you.
3. Use a commercial SMTP relay host.
4. Have the users send mail directly to the ISP's host using their mail client.
> PS: With proper SPF, can I send directly without being considered a spammer? I've never really figured out SPF...
Nope, SPF has nothing to do with the blacklisting of mail from dynamically assigned IP addresses. Good grief, I expect more spammers are using SPF than valid mail sites.
> I have a dynamic IP from my ISP which means I don't want to send my own email, as some people consider mail from dynamic
> automatically spam.  
Anybody using the Spamhaus-ZEN blacklist will reject mail from dynamically assigned IP addresses.  Many other blacklists also use this technique.
> Furthermore my ISP restricts the number of unique FROM: email addresses when sending to 10 and I have to register all email addresses that will
> be used for sending.  I run a small business and this limitation of max of 10 outgoing addresses is hurting me.
How about getting a fixed IP address.  Is the cost that much more than the dynamically assigned IP address.  
>
> I see two solutions: 1) is to pay for a SMTP service to relay the mail for me.  I've done that in the  past, and it's ok, but they're
> expensive.
I'm not all that sure it's all that expensive.  DynDNS costs ~$15/year for 150 relays and you can buy this in blocks to increase the limit.
https://www.dyndns.com/services/sendlabs/outbound.html
> 2) my ISP (Rogers in Canada, which is in cahoots with Yahoo by the way) allows multiple mail boxes, so I've been thinking that I set up
> a mail box for each employee.  But this means that the Mercury Relay SMTP client somehow has to send to the correct Rogers/Yahoo mailbox
> depending on which of my employees is doing to the sending.  And I don't think it can do that.
The employees could bypass Mercury when sending and send directly the the Yahoo host.
> So then plan B was to run multiple Mercury's - one for each employee.
A real pain in the rear!
> But this becomes a nightmare to administer, and I've been running Mercury forever (10 years+) and how do Itake the various user
> sections apart into separate folders for each mercury?
> So do you have any suggestions on how I can solve this?
1.    Get a fixed IP address.
2.    Talk to your ISP and tell them you are running a business and the outbound limit in killing you.
3.    Use a commercial SMTP relay host.
4.    Have the users send mail directly to the ISP's host using their mail client.
> PS: With proper SPF, can I send directly without being considered a spammer?  I've never really figured out SPF...
Nope, SPF has nothing to do with the blacklisting of mail from dynamically assigned IP addresses.  Good grief, I expect more spammers are using SPF than valid mail sites.
