Sweeping Multibit Classic Key: Private key outside allowed range

[bitcoinmedic]

Hello!

I have a very strange problem when sweeping keys of Multibit Classic:

There are four private keys in my Multibit Classic configuration:

Code:

5JGXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXr4PA 2009-01-03T18:15:06Z # 1KXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx7
5JGXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXsiKg 2009-01-03T18:15:06Z # 1VXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX6
5J6XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXreqU 2009-01-03T18:15:06Z # 1NXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXqz
5KmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX388P 2012-08-29T21:20:01Z # 1FXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXxh

(The XXX are changed by me)

I can sweep the first three keys, the fourth key however causes problems with bitcoin-cli:

Code:

$ bitcoin-cli importprivkey 5KmXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX388P w1
error code: -5
error message:
Private key outside allowed range

Also Armory shows an error using this key:

Code:

Invalid Private Key 
The private key you have entered is actually not valid for the elliptic curve used by Bitcoin (secp256k1). Almost any 64-character hex is a valid private key except for those greater than: 
fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141 
Please try a different private key. 

Did anyone have this problem before? Was this a bug of the key generation of Multibit Classic?

Are the funds lost?

[1715008783]

1715008783

[1715008783]

1715008783

[HCP]

Honestly, I have not come across this before... and I don't remember anyone else posting that MultiBit had generated an "out of range" private key. I haven't been able to find anything in the MultiBit github issues list (open or closed) either.

Have you tried inputting the key into an "offline copy" of https://bitaddress.org (click on "Wallet Details" tab) and seeing what addresses it generates?

[NeuroticFish]

I used Multibit classic long ago and I moved all my keys long ago into Electrum. I used the export function and then used the exported keys in Electrum.
Your lines look familiar, but without the ending comment with the address. Did you try to get the 4th key into Electrum (standard wallet -> use public or private keys...)?

Another attempt would be (after backing up everything) to try to start Multibit classic (maybe in a VM with same config files?) and see what I can load, what can I export and whatever cannot be exported correctly, maybe I can move the funds to another address.

I hope that at least one of the 2 ideas helps. Good luck!

[bitcoinmedic]

Thank you for the answers.

In bitaddress.org tool it states "BigInteger is outside of curve range".
I also have tried everything in the old MultiBit classic software, I just does not release the transaction correctly.
All the other keys work perfectly fine.

[HCP]

If that is the error being thrown... then your private key is basically invalid. Private keys are really just very large numbers... and unfortunately, it would appear that yours is a bit TOO large

As you have theorised, it is probably an old issue with MultiBit that was never noticed before the Dev's dumped it in favour of MultiBit HD.

Sadly, I don't think you're going to be able to recover the coins on this address.