A Search Engine Watch Forums thread accounts a Microsoft adCenter advertiser getting billed over $1,500 after having paused an ad he was running. Not only that, he paused the ad over 60 hours ago and the ad has yet to be paused. This means, that until the ad pauses and is removed from MSN Search and Windows Live Search, the advertiser will continue to be billed.
The advice given?
get aggressive! Just cancel your credit card. Or take a much more drastic action, close down your account and contact help center to open a new account.
Forum discussion at Search Engine Watch Forums.
Update: Also more frustration at WebmasterWorld.