The Close existing HaloPSA Quote as Won! window will appear so you can review and make changes to the completed sales opportunity before it is created in HaloPSA. This includes the Status, Agent, and Notes.
The opportunity will automatically be set to Opportunity Won and the status will update based on your selection above.
When you're in HaloPSA, you can find the Sales Opportunity by either choosing the Opportunities option on the left hand menu or you can open the associated Customer and click on the specific Opportunity under the Opportunities tab.
When you're saving changes to an existing order, a Create/Update Completed Sale checkbox will appear on the File->Save window.