Help with Chessbase 16 "No games found"

Hi all. I've just acquired Chessbase 16 and the 2020 Mega Database, both of which I've installed on my laptop. When I enter a position via "board", and then press "reference", it says "Big Database: no games found". What am I doing wrong? FYI, the Big 2020 Database appears in the reference database window at the top in the middle, and the database itself is toggled as "reference DB" in properties. I'm sure it's something sill I'm doing (or not doing!) but need help getting going. 

Thanks in advance. 

Hi. I have absolutely no idea. I'll check (though I don't know how to do that).

You need to install the Megabase (not bigbase), and the megabase will show up as "Megabase 2020". Then you right click it and choose reference database.

Bigbase and Megabase are two different things.

And why aren't you using megabase 2024 or 2025? There's a whole lot of interesting lines played since 2020 in classical (even if the new # of games since then is overwhelmingly titled tuesday blitz games and other rapid games).

Hi. Yes, I've done all of that. I've installed the Database, tagged it in "properties" as reference DB etc. Still turns up "no games found" even though, when I go into the Big Database 2020, there are millions of games.

To be clear on the wording (apologies for not getting the name right the first time), I have the Big Database 2020. The reason I have that and not a more recent one is that I got all of this software in an auction (Chessbase 16, the Big Database 2020, Opening Encyclopedia 2020, Fritz 17 etc. etc. etc) for $5. It's the software I have, and I can't afford to buy updated ones new because they are very expensive.

Update: I exited the program, started it up again....and voila! It's working fine. Thanks for help and suggestions.