Well I'm afraid I'm not sure how to turn off error messages on screen but I do know how to stop error messages coming up on running scripts (don't make any mistakes) in VBScript you can use an
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on error resume next
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statement as this will just skip the command that create's the error.
This is only viable in ASP though so it's not much use.
All I can think is that such a script should not be needed as error's can be fatal and so Error messages are shown for a reason!
Sorry
Owen