Quote from: evergreentrone on May 03, 2021, 07:42:33 PM

I have a problem and maybe you can help me

So, many years ago (2013) i used multibit on my mac. I just opened multibit, create an adress and used it to transfert bitcoin. I never used a password. During 2 years i send bitcoins 1 time per month. One day (2015) i sended bitcoin on my multibit adress before open multibit. When i opened it, SURPRISE ! the bitcoin adress had change ! and there is no bitcoin money. When i checked the public key i see the transfert and bitcoin money.

Sounds like you opened a different wallet file... MultiBit Classic (and HD) had the ability to create multiple wallet files. MultiBit Classic could also generate multiple keys/addresses, even tho it wasn't an HD wallet... it just generated "Random" keys that were unrelated to each other and not derived from a seed.

Quote

When i try to recover wallet or key in multibit file, nothing ! so after read some articles, i exported private key ... (too late).
Now we 're in 2021, i find my multibit wallet from 2015 with the new adress. I try software to recover old multibit file from when i created the wallet but not files .wallet or .key ...
I have a chance to backup my old wallet ? Huh

If when you look at the old 2015 wallet with the "new" address... you don't see the "old" address on the "receive" tab, then it definitely seems like you opened (and subsequently kept) the wrong wallet file Undecided

Unfortunately, if you are unable to file any .wallet of .key files, then the changes of being able to recover your "old" private key/address are pretty much zero Undecided