Canceling Orders
Depending on the order type and the time of day, a player may have the capability to cancel an order from being executed. Please realize that limit and stop orders can always be canceled prior to execution. Due to the nature of how basic market orders are supposed to behave, they cannot be canceled.
The only exceptions are for MARKET OPEN orders (a special class of market orders that are made when the markets were closed for trading), which can be canceled before the markets open for trading.
We will now go through an example about canceling an existing sell limit order for Wal-Mart (WMT). (If you need to review how to make a limit order, click here).
First, click on the Portfolio tab and scroll to the bottom of the 'Holdings' section. You will see pending trades. You will see that Microsoft (MSFT) is not cancelable since it is a market order.
To cancel your pending trade, click on the corresponding "cancel" link to the right of the stock you are trying to sell (in this case, its the one for WMT) to initiate the cancel. You can click the 'Cancel Order' button to proceed with the cancellation.
In the case of limit and stop orders, cancellation does not happen instantly. It will typically take around 20 minutes from when the cancel request is initiated before the order will be removed. If the target price is met during those 20 minutes, the order will still go through. Market open orders, on the other hand, will be instantly canceled when the cancel command is selected.