Can old wallet.dat (offline long time) still receive money? I have an old wallet.dat file (from a backup) and no client installed since a very long time. Recently some transactions have been made (BTC have been sent to my address).

Will this old wallet.dat file allow me to be the owner of the new money? I’ve read that 100 private keys are generated in advance and are in stock of the file. Does that mean, that I can receive 100 transactions after taking my client (it was bitcoin-qt/bitcoin-core) offline? Or what are these 100 keys for?
Can old wallet.dat (offline long time) still receive money?


Yes. If you have the addresses from that wallet, coins can be sent to those addresses.


  I think that I remember that 100 private keys are generated in advance and are in stock of the file. Does that mean, that I can receive 100 transactions after taking my client (it was bitcoin-qt/bitcoin-core) offline?


An address can receive coins more than once, although it's considered best practice to try to avoid that. But, in practice, you can receive many transaction that pay to any of those 100 addresses.