Prospecting missions using the scanner provided by the mission and with no other scanner involved is allowing the mission to complete and rewards given but is not granting credit under Character --> Statistics toward the 120 Prospecting missions about 50% of the time. The missions log shows the correct number of completed prospecting missions listed individually.

This use to be a off by one error...
Have you checked to see if the total is right after you re log?

Ahh it updated after client refresh, thanks much. So I guess the bug is just a refresh problem with a workaround of restarting client.

Generally it updates when you leave the sector as well.

I know I'm late to this thread, but glad I found it. I was worried that I was doing something wrong. Glad to see that my count tallies up after all!