When you want to close a proposal, you can do that through the Details page. All of your In Progress and Past Due proposals will appear on your Dashboard until you give them another status.
You might change statuses for reasons like:
We chose not to bid on it (No Bid)
We missed the deadline (oops, that's happened before...No Bid)
We completed it, but haven't heard back yet if we advanced (Complete)
Changing a proposal to No Bid, or one of the Complete statuses (Complete, Complete - Won, Complete - Lost) will keep the open tasks from notifying your users. So they won't be reminded of open (incomplete) tasks. We silence those notifications.
On the right-hand side of the Details page, you will see a drop-down with multiple options.
Not Started
In Progress
No Bid
Complete
Complete - Won
Complete - Lost
Click on the drop-down menu to update the status of your proposal to one of the options listed above.