I've been using Loki for about 3 weeks. Installing software and updates was working fine. I booted into Loki today and got a notification that I had 4 updates available. The red flag also appeared on the App Center icon on the dock. I launched App Center and clicked on the Update tab. The Update window had the following error message: "No Results. No apps could be found. Try changing search terms."
I also tried to install two different software programs: virtualbox and gdebi. I tried them each separately. I had the same result both times. After clicking on the Install button the Starting progress bar appeared. I waited 5 minutes with each program and nothing else happened - no progress was shown on the progress bar. I clicked the Cancel button and the installation was canceled each time.
I have no idea as to what I should do next. Anybody have any suggestions?