# Connection from Sparrow to Bitcoin Core NOT WORKING after update from 0.4.0.0 to 0.4.0.1
**URL:** https://community.start9.com/t/connection-from-sparrow-to-bitcoin-core-not-working-after-update-from-0-4-0-0-to-0-4-0-1/5496
**Category:** Services Support
**Created:** [August 3, 2026, 9:42am UTC](https://community.start9.com/t/connection-from-sparrow-to-bitcoin-core-not-working-after-update-from-0-4-0-0-to-0-4-0-1/5496 "2026-08-03T09:42:40Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Robert\_Hobbes](https://community.start9.com/u/Robert_Hobbes)
#### Post date: [August 3, 2026, 9:42am UTC](https://community.start9.com/t/connection-from-sparrow-to-bitcoin-core-not-working-after-update-from-0-4-0-0-to-0-4-0-1/5496/1 "2026-08-03T09:42:40Z")
I am/was using Sparrow wallet to connect to start9 node for balances and transactions.
all was fine on 0.4.0.0, but after update to 0.4.0.1 it is not working.
Setting for 0.4.0.0 start9 on Sparrow where
URL: twnyjosjh52yoqkj7hvx6n34evpvon43y7a3msufg346phwjyqltm4id.local 443
User / Pass: bitcoin /appropriate\_password
When I do
```auto
nc -v twnyjosjh52yoqkj7hvx6n34evpvon43y7a3msufg346phwjyqltm4id.local 443
```
I get
```auto
nc: getaddrinfo for host "twnyjosjh52yoqkj7hvx6n34evpvon43y7a3msufg346phwjyqltm4id.local" port 443: Name or service not known
```
OK I understand that after updated to 0.4.0.1 this is not name for star9 node any more.
I have tried all combinations from
Services → Bitcoin Knots → Interfaces → Peer
Services → Bitcoin Knots → Interfaces → RPC
And still can not connected.
Even when generating new user
Services → Bitcoin Knots → Auctions & Config → RPC Users → Generate RPC User Credentials
I have same errors.
What means that I am still using wrong port number ?
I will documents all URL/PORT combinations, with error from Sparrow “Test Connection”
but all these are working from nc -v, what meant that URL and port is correct, but it is just not correct interface.
```auto
# from Services → Bitcoin Knots → Interfaces → Peer
little-stoops.local 51004
192.168.1.110 51004
# error
Could not connect:
Invalid Http response
# from Services → Bitcoin Knots → Interfaces → RPC
little-stoops.local 55888
192.168.1.110 55888
# error
Could not connect:
Cannot invoke "com.github.arteam.simplejsonrpc.core.domain.ErrorMessage.toString()" because "" is null
# with original 443 port, port 80 is giving same error
little-stoops.local 443
192.168.1.110 443
# error
Could not connect:
Unrecognized token 'Method': was expecting (JSON String, Number, Array, Object or token 'null', 'true' or 'false')
at [Source: REDACTED (`StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION` disabled); line: 1, column: 7]
```
Hopefully somebody have figured it out.
And can tell me what to do.
---
### Author:  [@Alvaro](https://community.start9.com/u/Alvaro)
#### Post date: [August 3, 2026, 10:25pm UTC](https://community.start9.com/t/connection-from-sparrow-to-bitcoin-core-not-working-after-update-from-0-4-0-0-to-0-4-0-1/5496/2 "2026-08-03T22:25:06Z")
You should try installing the Fulcrum service and connecting Sparrow Wallet to its Electrum SSL Interface.
First Local IP:Port
It works great.
---
### Author:  [@Robert\_Hobbes](https://community.start9.com/u/Robert_Hobbes)
#### Post date: [August 4, 2026, 5:08pm UTC](https://community.start9.com/t/connection-from-sparrow-to-bitcoin-core-not-working-after-update-from-0-4-0-0-to-0-4-0-1/5496/3 "2026-08-04T17:08:05Z")
Familiar with Fulcrum, just overkill in my use case.
Also have issues with [Bitcoin ZeroMQ and RPC, after update from 0.4.0.0 to 0.4.0.1 --- not working](https://community.start9.com/t/bitcoin-zeromq-and-rpc-after-update-from-0-4-0-0-to-0-4-0-1-not-working/5489)