Hi Tim,
OK, the mystery has been solved. I used ProcessMonitor as suggested by you, and it turns out that it is my AntiVirus/Spyware/Firewall from CA that is removing the files every hour at about 14 minutes past the hour (specifically the process cctray.exe). I'll be selectively disabling them until I find out exactly which one and why it is - I mean, who do they think they are anyway !
So thanks for the pointers, and hopefully I haven't wasted too many people's time on this one.
Regards,
Steve.
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