Updated: Feb 16, 2020
The ITN Daedalus update is here but there are a few minor issues. It is a testnet after all and I reckon whatever doesn't kill us makes us stronger!
Anyway, you're here because you are seeing the "wallet already exists" error and you would like to resolve it.
Don't Trust - Verify, Always! Proceed at your own risk.
NOTE: This fix requires that you have a backup copy of your 15 word recovery phrase in order to recover your wallet. If you don't have this recovery seed available then you have an even bigger problem than a wallet not working properly!!
[Workaround assumes Windows 10]
Before proceeding make sure Daedalus - Rewards v1 is stopped. The best way to ensure this is to do a reboot now . . .
Step 1 - Make a backup copy of the "Daedalus - Rewards v1" folder in case you need to revert:
Navigate to "C:\Users\%USERNAME%\AppData\Roaming\"
Right-click on the "Daedalus - Rewards v1" folder and select copy. Next right-click and select paste to make a copy.
You should now have the original folder and a backup copy, like so.
Step 2 - Remove [most of] ITN Daedalus State Directory:
I say 'most of' as I have managed to resolved this issue without deleting the pre-existing blockchain storage. This saves time re-syncing the entire blockchain. Having said that, if it doesn't work for you without deleting the "chain" folder then just delete it and grab yourself a coffee or three whilst it resyncs.
Navigate to "C:\Users\%USERNAME%\AppData\Roaming\Daedalus - Rewards v1"
Select and delete everything within the "Daedalus - Rewards v1" folder except for the "chain" folder.
Step 3 - Start "Daedalus Rewards v1" app
Follow through the usual prompts for 'first run' of ITN Daedalus - specify your date and time preferences and agree to the ITN Daedalus TOS.
Now you can re-create your ITN Daedalus Rewards wallet from your 15 word recovery phrase. The one that you definitely NOTED down and saved in a safe place when you setup your ITN Daedalus 😉. Rinse, repeat for additional wallets.
It will take a while to sync your wallet against the blockchain. If wallet syncing stalls you may need to restart ITN Daedalus a few times before you get to 100%.
If you still have issues after the above then you can always try Resync wallet.
Lastly, blockchain storage can get corrupted from time to time. If you continue having issues adding your wallets it probably means you'll need to try this again but this time delete the "chains" folder as well. This will sync a new copy of the blockchain.
The above process worked for me (several times) for the 15 word recovery for Rewards wallets. I haven't tested it with the 12 word recovery for Balance wallets.
EDIT: Kaizen Crypto has now added a YouTube video for Mac users:
IMPORTANT: Make sure you do all this in the relevant ITN Daedalus folder, not your Mainnet Daedalus!! For Windows 10, the correct folder for ITN Daedalus is "C:\Users\%USERNAME%\AppData\Roaming\Daedalus - Rewards v1".
Hope this helps . . .
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