problem solved, the C:\ProgramData\Microsoft\eHome\mcepg2-1.db had grown to a very large value, in excess of 600M bytes. The SQL epg data base was not corrupt just very big, since i turned off automatic mcupdates in 7MC a long time ago.
the solution was to simply do a EPG SQL garbage collection to re-claim all the EPG entries marked as deleted.
C:\Windows\ehome\mcupdate.exe -dbgc -p 0
once the database garbage collection completed, the EPG database size was reduced to a mere 50M bytes, and now ehshell.exe happily has no excessive cpu cycles when accessing the EIT EPG...
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1. open up a DOS command prompt ( press start then type in cmd ), this will upen up a command prompt.
2. type this command in 'C:\Windows\ehome\mcupdate.exe -dbgc -p 0' without quotation marks. The command will execute and fork into the background and return your command promt controll back to you. Leave the prompt open until step 4 below completed.
3. The process of EPG SQL database garbage collection, will start when you see the below event viewer message ( in Applications and services>Media Center )
Log Name: Media Center
Source: MCUpdate
Date: 3/08/2012 3:50:05 PM
Event ID: 0
Task Category: None
Level: Information
Keywords: Classic
User: N/A
Computer: HTPC
Description:
3:50:05 PM - Starting Client Maintenance.
The process will take several minutes for a large SQL database such as yours.
4. The process when completed will log the below event viewer log message, again in in Applications and services>Media Center
Log Name: Media Center
Source: MCUpdate
Date: 3/08/2012 3:50:39 PM
Event ID: 0
Task Category: None
Level: Information
Keywords: Classic
User: N/A
Computer: HTPC
Description:
3:50:39 PM - Client Maintenance has completed.
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