In good news, it is unlikely that the Slingbox has stopped working completely. In situations like this, it is very likely just the power supply unit that is no longer working and replacing this would fix the issue. I've linked an article below that discusses this issue, just in case you would like to try a few other steps as well:
If you would like to purchase a new power supply first, or have already tried the other steps listed in the article, you can purchase this accessory using the link below. In the event that your exact model is unavailable, the Slingbox 350 power supply will work perfectly for the model you have noted in your original post.
I hope this helps!
Sling Media Technical Support
Thank you so much for your response. I have a question for you though…..
Even though the network light won’t come on the horseshoe light is completely lit up with no activity. It seems to me that there is sufficient power but I am happy to try another power supply if that is what you think.
Let me know.