Last used in 2015. When I went into qt to update now, update took 5 days then crashed due to a "windows error" (Did this twice) - so I downloaded Core, and of course, it doesn't have my bitcoins in it. There is no .dat file that I can see in the bitcoin directory (and I can't even find the core directory) - Sorry to seem so confused. There's a daemon folder, a doc folder , the bitcoin-qt app, a copying file and a readme file. - and an uninstall. I'm on windows 7, computer states is 64-bit.
The blockchain and your wallet file are stored in the Bitcoin Core data directory. This directory is different from the install directory where all of the binaries are. When you start Bitcoin Core, go to Help > Debug Window and see what folder it is using as its datadir. Make sure that that is what you expect it to be; if you have changed the datadir (by choosing a different one when you first started the client), then make sure that that is what Bitcoin Core is using. Otherwise it will use the default datadir of