You may remember that last year I had some problems with EHM 2007 crashing when trying to load it. Suddenly it started working again one day and all was well.
Then it stopped again, and I haven't been able to play since

Then my PC went a bit odd and I ditched ZoneAlarm for Comodo.
Lo and behold...it's working again! I don't understand what went wrong before but it looks like ZA blocked some process without telling me and messed it all up.
So I can play again...hurrah!! I hope this helps anyone else who had this error and never managed to fix it.