Computer A: wallet.dat is corrupted, you should :
(found for windows)
1) create a folder named protoalt and keep it's path in mind
2)Copy all the files except your wallet.dat into the new folder
3) Create a .bat .sh to start the alternate you have created
3)start your client with -salvagewallet, this does exactly that.
4) once your wallet is recovered, start the alternate client, it will create a new wallet for you.
5) send coins to new wallet and use it as main one now.
Computer B: Database corruption, relaunch core with reindex=1 in bitcoin.conf and try it.
These are brand new wallets, I'm trying to get the app to sync from scratch, totally clean and fresh. I do have my old wallet files but this is before I even get to the point of trying to get at those coins.
no problem, you can go with it even if new wallet.dat, sometimes it happens on fresh install, either on mac windows, linux or any other.