Thanks to both of you for your replies.
Paul, I'm glad to see that we're on the same page about not liking to see this situation. And of course it's not a personal insult. Rather, it's an insult to everyone who has legitimately purchased VSL products: it wouldn't be so bad if the process of scanning licenses was nearly instantaneous, but it takes an exceptionally long time for the licenses to be validated even when the key is present! That said, I reinserted the key anyway (as Dietz suggested) but then got the error message you see below. It was impossible to click "OK" because when the mouse pointer hovers over that error window, it turns into the SBBOD.
BTW, this error message has remained persistent on my screen ever since I posted this thread yesterday, with no obvious way to force quit whatever process is generating it.
Sigh...