Dymanic ISP IP addresses and SPAM filtering

[Belix]

Hi guys
Just had a irritating two days trying to figure out something:

Friday, ADSL goes down and red "internet" light appears on ADSL router. Call telkom, who announce local exchange has issues.
Reboot router, red light stays on, but internet now seems to work fine. However, suddenly can't send emails, all bounce back with errors of all descriptions. Phone syncing with exchange server stops working. Decide to wait on telkom...

Monday moring, same light on modem. Call Telkom who announce nothing wrong with exchange. reboot router. Red light goes out, but internet connection dies. Reboot netgear GT834 again, red light appears on again, but full internet access returns.
Phone syncing with exchange server erratic on and off
Checking through email error messages, I see that the recipeint mail server is blocking the mails. WTF? Why suddenly?

It seems that when I reset the router, IS assigned us an IP address that is blocked by the majority or spam monitoring sites around the world.

Tuesday, turn off modem for an hour in hope of getting a different dynamic IP address. On reconnection, different IP address!! Email sending now ok, but active sync with phones still very erratic, and some phones don't connect at all. Red light on modem still on...

Firstly, from what I hear, most dynamic IP addresses are blocked by spam sites which is why we use a trusted intermediary like Mail Marshall or the ISP SMTP server to send. So why does did the emails bounce int he first place? They bounced with the IP address of the IP asigned by IS, NOT the Mail Marshall IP, so it seems the spam filters are reading through all the headers now??

Second, any ideas what gives with the active sync? is there a way I can check the server to find if the phones are getting through at all?

Thanks guys

[Belix]

OK seems Internet Solutions are the morons at fault.
I've learnt they suddenly, and without warning, cahnged their policy about multiple logins last week. It seems that remote access to webmail, as well as the connection the phones make to exchange are somehow seen as a seperate login. So they killed that, and killed the web access and active sync at the same time...

What has this got to do with the red light?

Well it seems the netgear modem does not let you tick PPPoE Relay (better known as bridge mode) unless you select PPPoE in the basic screen. Selecting that requires a password and username, which I entered. Hense the modem was actually making two connections at the same time, one itself and the other in the bridge mode from the server. When the idiots at IS made their changes, it only allowed one connection. The the modem directly made the connection, the light was green, but the server could not seem to access the internet seemingly because it had not initiated the connection. When I reset it, the server sometime made the connection first, and we got connection. However, the modem then tried to make it's own connection, could not, and hense gave the red light.
Anyway, have since found that you can select "no login required" on the basic screen after selection PPPoE Relay, which kills that internet light completely.

All in all, many thanks to Internet Solutions for the *** I've been through for the past 5 days...

Would still like to hear how the dynamic IP addresses work.