Ketchup, is it showing as still using zap2it or Rovi? I was using vista also and had to manually edit the hosts file and ipconfig /flushdns then it started using Rovi but I also had to try different zip codes until I found one that works.
from green button forum posted by HDTV-WC-Fan
The problem is that WMC does not know where to find the data for the EPG. Around July 26, 2015 Windows change data providers from Zap2It to Rovi. Microsoft and Rovi were ill prepared for this changeover. To do the changeover WMC needs to change from the Zap2It to Rovi for its’ Guide. WMC should change data sources by running WMC Setup. Setup fails to change data sources for three reasons.
1) Setup cannot complete this task until it recognizes Rovi as the guide.
2) Rovi needs a valid zipcode, and this is important, that Rovi is providing data for
3) WMC needs to know where get to Rovi data
Let’s solve issue 2 first. Rovi’s zipcode data base has massive holes. To find a zipcode that will work for you. Go to MSN Website populated by Rovi data and find a working provider.
http://www.msn.com/en-us/tv/tv-listings
In the search menu keep entering cities till the drop down menu produces a provider that will work for you. Most cities will not provide an OTA option. Since Setup will not accept cities you still need to find a zipcode within that city that will work. (I live in Atlanta and had to use a zipcode from 30 miles away 30601.) Enter that zipcode make certain that the website populates with data that is useful to you. Write it down, this will be zipcode that Setup needs.
Now let’s deal with issue 3. Helping WMC find the Rovi data source on the web.
close WMC
click start button
type CMD in search box
right click CMD and run as administrator
cd c:\windows\system32\drivers\etc
notepad hosts
Add the following 2 lines
65.55.186.113 data.tvdownload.microsoft.com
72.246.56.59 cdn.epg.tvdownload.microsoft.com
(if there are other lines in your file that are for data.tvdownload.microsoft.com or cdn.epg.tvdownload.microsoft.com comment them out by placing a # at the beginning of the line)
save the file and exit notepad
in your cmd window
ipconfig /flushdns
click start button
in search box type taskschd.msc
after task scheduler opens
In the left tree expand Task Scheduler Library, Microsoft, Windows
click on Media Center folder to highlight it
In the upper window of the center section scroll through the activities under the Name column.
right-click ObjectStoreRecoveryTask, and click Run
Let this run for a minute or two
Reboot and re-open WMC. You will receive a warning that WMC corrected a problem and will download the Guide EPG data again
Tasks > Settings > General > Windows Media Center Setup
Use the Advanced instead of the Express option.
Remember to use the zipcode from the MSN Rovi website!
What is this is doing: 1) hard coding the lookup for data.tvdownload.microsoft.com and cdn.epg.tvdownload.microsoft.com. As soon as you put entries like this in your hosts file the DNS that you are using no longer matters. This eliminates the need to change your DNS to google or open DNS. 2) ipconfig /flushdns removes any caches entries for the items listed in your hosts file. 3) the task scheduler run removes your epg guide while you have a valid zip code. This forces WMC to completely re download the epg from the ip address listed in your hosts file.