I do these and salvage missions a lot and see this problem regularly too. Sometimes I go on to another system where I have the next black box or salvage op, do that one, then return AFTER I log out to main menu and log back in.* If I don't feel like taking the time, I'll just dump the mission.
A key to knowing if there's a problem is:
When you drop in to the target star system, your COVAS immediately announces that a "mission objective (is) detected." If you don't hear that, the mission site will not be able to be found. In my experience with these failures, leaving and returning does not create a good chance that the mission will work properly. It's not zero but it's quite low. I have tried the logging trick just a few times since it was suggested to me so I can't yet comment with certainty on its level of success. As I mentioned, sometimes I just don't find it worth taking the time to return. That's me...
With regard to using the FSS, I use this vastly more often than I stop at a nav beacon to find the mission site. In my experience doing many, many of these missions, it's just far faster at least 95% of the time than stopping at a nav beacon. I would suggest that it's well worth the time to get a hang of the FSS. Perhaps you can multicrew with someone who can help you with it.
* I know it's not a solution, but it does offer a chance that the mission will be do-able (not 100%, mind you). I saw a post in another thread that hinted at what the problem behind this is. If I find it, I will update here.
EDIT
A short thread. See post #3 if you don't want to read them all. I won't comment on the authoritativeness of the info- as I mentioned above, I'm still assessing its effectiveness. Cheers!
I took one of these missions and went to the system where I was to search. I scanned the nav beacon, but I didn't get any sort of mission update saying which signal source I was meant to fly to in order to recover the artwork. I also took a black box recovery mission at the same time (but...
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