Parts of the EPiServer Commerce API requires that you have an active HttpContext. This will make life hard when you try to call this methods from a scheduled job, one of these methods that require an HttpContext is the "Mediachase.Commerce.Website.Helpers.StoreHelper.GetSalePrice", it checks for a value in the users cookie and if none is found it will take a default value, but if the context does not exist it will just throw an null pointer exception and fail. To fix this I just added the following code to the start of my scheduled job,
if (HttpContext.Current == null)
{
HttpContext.Current = new HttpContext(new HttpRequest("index.aspx", "http://tempuri.org/index.aspx", string.Empty), new HttpResponse(null));
}
