Upvote:6
Assuming your nationality is one that requires a visa to visit Dubai, you should, as Tom so ably puts it: get a new visa. An expired visa will not be accepted, and the airline should not allow you to board unless you have the travel documents required for entry.
If there is not sufficient time to get a new visa, you will have to delay your trip, though you can always try conveying the nature of your urgency to the proper authorities if this trip is an emergency. If your nationality and purpose of travel makes you eligible for a visa on arrival or an e-visa, then you should pursue that option.