Question: I'm still new to map Usage.. How could this code be bulkified?

```
trigger OppyStatusCheck on Opportunity (before insert, before update) {
    for(Opportunity opp : Trigger.new) {
        if(opp.StageName=='Closed Won') {
            List<Quote> quoteChilds = [SELECT Id, Name from Quote where OpportunityId=:opp.Id and Status='Accepted'];
            if(QuoteChilds.size() < 1) {

                String errorMessage = 'At least one accepted quote required for closing an opportunity!';
                opp.addError(errorMessage);
            }
        }           
    }
}

```

Answer: 
Issues:

1. URL No Longer Exists
	* Error is happening because your path to the page is incorrect and is missing the leading `/` which creates a URL which is relative to the current page rather than relative to the host.
2. Path to the page outside of the managed package namespace
	* The default VF namespace is `c__` and you can specify this in your page path. This allows you to avoid hardcoding a fully qualified URI.

`<apex:commandButton value="Open" onclick="window.open('/apex/c__MyPage'); return false;" />`

Related: [How to redirect to default namespace vf page from managed package vf page?](https://salesforce.stackexchange.com/questions/22132/)
I think pages opened from within a managed package must always be fully qualified with the full URL, so your button would have to be:

```
<apex:commandButton value="Open" onclick="window.open('https://c.csXX.visual.force.com/apex/MyPage'); return false;" />

```

Obviously, this will give you some challenges to get the correct pod in your URL, but other than that should work.

I believe it is indeed a feature of managed packages.