I have recently come back to bitcoin due to recent events.

I was mining in slush's pool a few years back and racked up 13 BTC.

http://blockchain.info/address/e53d7762e8cf2989c24e79d5bcf6faa50cb4f06d

However, upon coming back I found that the client I was using would not sync. So I updated it and I no longer had the address or bitcoins.

I was using a client that looked like this and the address I entered was in that red box. (on my client not the picture).

http://bitcoinintro.com/wp-content/uploads/2011/09/OfficialBitcoinClientMainScreen.png

Any ideas on what might of happened?

Does a software update overwrite your wallet.dat?

Does a software uninstall delete your wallet.dat?