You got the error “Process INETINFO.EXE (PID=1748). Topology Discovery failed, error 0×8007077f. ”
On your event viewer after you changed the IP from your server, and you don´t know what is it.
This error can appear on DSQuery, OWA, OMA and others Exchange 2003 and 2007 Servers.
What this error means?
It means the Exchange Server doesn´t know wich site it is located.
There is a great possibility you don´t include the new subnet on the list of your sites..
So Let´s fix It.
1. Open Active Directory Sites and Services
2. Go to Subnets
Check if your new IP has an subnet there. If not Include it.
3. Include the new subnet (remember class c = 255.255.255.0)
4. Wait 15 minutes or replicate the server manually.
I restart the server just to make sure he gets the new info.
After that your problems should go away 
Any more questions enter in the forum.
