Till, Thanks again for your response.
Couldn't get in with external IP address but switched to internal address and got in.
When I got in here's what I did:
Changes in ISPConfig: Service was dynamic and now is static. Changed Server Config IP address to new external address (was internal address), Netmask to specification ISP gave me, and Gateway was internal (192.168.0.1) and changed to external specification ISP gave me, Host Name remains the same, Nameservers were changed to new ones for new ISP.
Changed all my DNS records for all sites to new IP address as well as template.
(Also Changed Router Internet Setup from Auto Configuration DHCP to Static IP and entered all the specification given to me by ISP, same as the ones I entered in Server Config above. But my local network address server setting is still set DHCP Server enable)
All native PHP HTML sites working fine.
- WordPress sites work but all take way too long to come up. It wasn't like this before I switched IP address. Do I need to reinstall these WordPress sites?
- Mail is still not getting out of my system, but still works internally. My server can't send or receive mail to the outside.
New ISP assures me that port 25 isn't being blocked. But it was working and now it's not working. Does Debian automatically update itself and could it overlay something? What can be wrong?