Figured it out. Just in case anyone else has this issue…
I purchased the downloadable upgrade of Wavelab 8. According to these forums, the Elicenser should upgrade automatically. I was able to open Wavelab 8 for two days after upgrading, though I did not spend more than a total of 30 minutes in the program.
Then, Wavelab 8 would not open because of this message:
"Application ‘WaveLab 8’ has caused the following error:
eLicenser(s) contain(s) no valid license for this application."
In the Elicenser program, I noticed only a key for Wavelab 7, not 8.
To fix, I had to find the email that was sent by Steinberg when I purchased the downloadable Wavelab 8 upgrade. I copied that activation code (a different code than my Wavelab 7 code). I opened the Elicenser program and clicked the button “Enter Activation Code,” entered the Wavelab 8 code and followed the instructions. Problem solved.
To sum up, the downloadable upgrade DID NOT update the Elicenser automatically.