ok I have just reinstalled this version. Can I do anything to recover my bitcoin?
Confirmed transaction cannot be reverted, unconfirmed transaction can potentially be cancelled by doublespending the inputs of the unconfirmed transaction and broadcasting the doublespending transaction to as many nodes as humanly possible. This is something that's really hard to perform for a non-technical person, and even if you succeed in creating a double spending transaction, the odds of getting your tx in a mining nodes' mempool are really, really, really small (so the odds of success are really low).
Even if the transaction is unconfirmed, most of the time it isn't even worth the effort to try to create a double spending transaction... Only if we're talking about a thefth of several thousands of USD worth of BTC it becomes something you can try as long as the tx wasn't confirmed.
I guess you should focus on what went wrong... When you say you reinstalled "this" version, which version do you mean? Where did you download it from? Did you check the signature?
Also, addresses that "magically" change are never a good sign... Is your pc clean? do you install software from unknown sources? Do you have a virusscanner running? Is your OS patched?
