SepticSceptic

Thanks Steve - I did miss out the vital DWORD key in my post, but yes, it is the PeriodicScanEnabled set to 0. I havent changed / created the other key as yet, but so far my guide seems to be intact with only the first registry key change. Though I seem to have lost the colour coding in the listings - I'm sure it was an EPG Collector setting that I had in the past that created the colour coding. But no biggie, I'm happy now that the guide data is remaining consistent, for the time being :-)

I'm wondering if it's a recent MS Security update that now prevents any changes to the registry by an external app ? This whole issue started in the last 6 months of last year.

Yes - tried running as Adminstrator as well - log shows Privilege Level:Administrator. A bit of web searching shows that this is the appropriate reg key ? HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Media Center\Service\BackgroundScanner. Creating a DWORD=0 and reboot is supposed to disable any in-band scanning. However it needs to be set back to 1 if there is a requirement to re-scan for channels.

Hiya Steve, OK - looks to be that is the issue, in the logs: 13:56:17:629 Opening registry key Software\Microsoft\Windows\CurrentVersion\Media Center\Service\BackgroundScanner 13:56:17:652 <E> An exception of type SecurityException has occurred 13:56:17:674 <E> Requested registry access is not allowed. 13:56:17:778 In-band guide loader may not have been disabled - check the registry

I have a similar issue with the DVB-T twin hauppauge tuners in conjunction with Windows Media Center, that has been driving me a bit bat-shit over the last 6 months. It's definately not the EPG, but I suspect that there is some in-band tuning or collection via WMC that is interferring or over-writing the EPG collected data. NZ - I would get full a week data for all channels, then suddenly they would drop to only showing the next program, or they would drop altogther. It seems to happen in "batches",...