Error in importing old paper wallet to Zecwallet fullnode

I generated a paper wallet back in 2018 and now I want to move the Zcash on it to better wallet. When I go to import the private key I get a “Invalid private key encoding” error and I have no clue what steps I need to take the fix this.

Make sure the syntax is correct, the whole key includes the secret-extended words at the beginning and no quotes (I think)
A successful import requires a rescan so if it doesnt automatically (dont know if it will) simply add
to the conf and restart then just remove that line so it doesn’t rescan the subsequently next time you restart

I have double checked the key and I have even tried scanning in the QR code for the private key and still get the error. Was there a wallet conversion sometime after 2018 I am not aware of? This was the wallet generator I used back in march of 18 ( I tested the importing process with a new wallet from the same site and it worked. The only think I can think of that might be a problem is that there is password on the one I am trying to import.

Ill try and see what I can see, it does have a BIP38 passphrase option

T import works, z import fails with invalid spending key but the code repository was last updated 2 1/2 years ago so yeah maybe…rescanning now

Importing a z address using an up to date paper wallet works

The addresses created with walletgenerator[dot]net dont and that website shoyld NOT be used

If you used a browser based key generator, then your compressed key should start with the letters L or K.
If it starts 6P, it is BIP38 encrypted and the key must first be decrypted first and then use the L or K address (compressed).
If it starts with a 5, it is an uncompressed key - use the wallet details to see the compressed version.

When you import a compressed key into ZecWallet, just enter the key by itself.

Here is an example created from (used random generated address).


In addition, if you do have the private key, it would probably be a faster and safer idea to sweep the keys to another wallet. This is not something Zecwallet has a UI for. Assuming the key is a T transparent address, you can use a third party wallet like Coinomi to move all funds from the private key to a new wallet in a few seconds (at the cost of a network fee).

If your key is a shielded one, then you should import the key and rescan. Using the Lite client might be faster if you know around what block the key was made as the lite client will start scanning from that block.

Please do some research on importing keys vs sweeping along with possible issues with change addresses.

How long did it take to decrypt the address? I am trying on my end with what I am 90% sure is the passphrase and just spins it little thinking wheel forever.

Update: Tested that you can use either compressed or uncompressed WIF keys. You cannot use BIP38 (6P) encrypted keys. Decrypt it first.

It takes an 3-5 year old Core i5 about 5-10 seconds at longest to decrypt. You should NOT be using the live web site for this function.

Download the version from Github, extract the files to a secure computer, and open the index.html from your computer’s file system in a browser.

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Yeah, the decode only works when its downloaded. I was going to move the Zcash immediately to a new wallet so I was not really concerned about security. So I tried the password that I even wrote “Zcash” next to and incorrect phrase. Just my luck, I’ll keep trying in the morning. Thanks for helping point out what I have been doing wrong so far. There is only like 0.2 Zcash in the wallet so if its gone its not a big deal to me, its just a point of principle to me now. If I cant guess it might look into smart brute forcing it.

Brute forcing BIP38 is NOT feasible unless you have a really good idea of what the password was already or if it was really short. The methods used in the cryptography are designed to be slow to thwart such attacks. There have been challenges online where someone posted their passworded key with 1 - 10+ BTC with no success.

Example from BitcoinTalk Forums - 2015 - 2017

First wallet was cracked in under 3 hours. [pwd: BarT]
Second wallet was cracked in under 10 hours. [pwd: grAce]
Fourth wallet was cracked in under 2 days. [pwd: pxrmg]
Third wallet was NOT CRACKED in two years. [pwd: zLwMiR]

Good luck!

Also, make sure Zcash is the Coin type in the top right. The BIP38 will be wrong if it’s for the wrong currency.

IM IN. Your comment about making sure I was on Zcash was the final piece I needed.Now I really need to go to sleep or my boss will put me through the rigger haha. Thanks a ton man. Its the little things that lock people out of there wallets XD. Though it is interesting that each coin does bip38 differently. Was kinda looking forward to hardware acceleration a brute force algo but now I dont need to anymore.

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Glad I could help and you got access. FYI I think the BIP38 encryption fails because it checks the output to match the coin key scheme.

1 year ago installed ZecWallet v 0.7.0. Now 9.08.2020 installed ZecWallet Fullnode on another computer and synced it. Then I imported the key from version ZecWallet v 0.7.0. I Received this message… Then I waited for a long time - 24 hours or more. However, my balance is still 0 Zec. What should I do?

Try replacing (copypaste) the appdata files with your old ones perhaps, you’ll have to reindex but wont have to import the key since its already in the folder
If it still shows 0 funds then I’d verify when they were sent (if you can see the address in question then the import probably worked and it may just be empty)

Do you know if there are funds in the address associated with your private key? If it is a transparent address (starts with t1…) you can check in a Zcash block chain explorer.

What is the current status in the lower lefthand corner of Zecwallet Fullnode?
Have you tried restarting the program?

If these have already been done, you will need to check the debug.log file for clues to what is going on with the program.

The file should be located at “%AppData%\Zcash\debug.log”.

You are looking for results that look like the following:

Note on rescan speed (18.55 minutes):
Your performance will be different based on your hardware capabilities.
The rescan in the image above was done on the following hardware/software:

  • Windows 10 2004 x64
  • Intel Xeon E5-1650 V3 (Haswell-EP)
  • NVMe PCIe SSD.
  • zcashd 3.1.0
  • The synced database used included transaction index.

If there was a problem, the log file would show some error or activity showing the problem around the time you import the key.

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Block Height - constantly updated, but very slowly
I reloaded the program - it didn’t help.
I didn’t find anything similar in the debug file.
How do I enable re-scanning?
I am a simple user and do not understand the software level.

To rescan add the line below to the conf and restart the wallet, remove it before the next restart


There are 2 things that can be tried.

  1. Rescan the currently downloaded blockchain.
    This will check each block using your private key(s) for any valid funds.
  2. Reindex the blockchain.
    This will use your CPU to verify all blocks from 0 to current and attempt to repair any damaged data found. A rescan should be included with this process.

If you are importing a transparent unshielded address, I recommend you verify the funds are associated with the address on the zcash blockchain explorer first. If they are there, you can use another wallet like Coinomi to sweep the funds into another wallet.

If you are using a shielded z address, you can do one or more of the following (one at a time). If one option works, you do not need to perform additional steps.

a) Re-import the private key (again) - this should start a rescan again.
b) Start a rescan manually.
c) Re-index your downloaded blockchain.

For item b), you have 2 options.

  1. Edit the zcash.conf file and add rescan=1.

The zcash.conf file is a text file that can be opened in notepad. It is located at %APPDATA%\Zcash\zcash.conf.

  1. Save the file and restart ZecWallet.
  2. Remove the rescan option from the zcash.conf file or it will perform a full rescan on each start.

The 2nd option applies to both items b) and c).

NOTE: The following commands assume a default installation using the Windows Installer Method (MSI Install File). If using the ZIP version, the path should be changed to the location of where the files were extracted.

  1. Close Zecwallet Fullnode.
  2. Run the following Command (Windows Key + R)
    %LOCALAPPDATA%\Programs\zecwallet\resources\bin\win\zcashd.exe -rescan
    %LOCALAPPDATA%\Programs\zecwallet\resources\bin\win\zcashd.exe -reindex

*You may open ZecWallet FullNode at this time to see any updates or changes.

It will take time to process the changes, but when done, I am not sure if closing ZecWallet Full Node will close zcashd.exe properly. To do this, run the following command:

%LOCALAPPDATA%\Programs\zecwallet\resources\bin\win\zcash-cli.exe stop

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