Alert system is crashing platform

 
Hello, is anyone esle having an issue where you are placing an alert to produce a sounds when the rate is reach and when processing the alert the system closes. I am able to set teh alert parameters but when I click submit, the platfrom is closing. If anyone has any informaiton about this I would be grteatful.
 
What's build of your MT ( menu help > about), and what's your OS (XP, Vista, 7) and it's SP.
 
I just set a couple of alerts (Terminal | Alert tab) on Build 419 using XP SP3. No problem.
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