damn... according to my .xls file at less 10k, I was not regular in my book... Yesterday I notice that I loose 40,3 dash (that was darkcoin at this time) I got them in my book but I'can't find the backup wallet... this is to much for me I'm really sad. Thank you for the information have a nice day
No matter which coin you have, you should always make a backup of the private key and store that in a safe place. That way you can never really lose your coins.
In this case a private key would not help. The old chain is no longer functional and all previous version coins were burned or swapped onto the new chain. Old dope coins are lost permanently but you are correct in the general sense... you should always back up your private keys.
Crypto wallets actually do not hold any coins, they are just a combination of public/private keys that allow access to your coins which are stored on the blockchain.