"Holochain sandbox running but getting 'Empty reply from server' on app port 9000"

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#1

Body:
Problem:
I have successfully started a Holochain sandbox using hc sandbox generate -r=9000, and my conductor is running. However, when I run curl http://localhost:9000/, I get the error:

curl: (52) Empty reply from server
What I Tried:
Checked that the conductor is running using hc sandbox list, and it shows an active sandbox.
Verified that the app is installed (test-app).
Checked logs with hc sandbox logs but didn’t see any obvious errors.
Restarted the sandbox with hc sandbox kill && hc sandbox generate && hc sandbox run.
Expected Behavior:
I expected some response from the app on port 9000, but it’s empty.
Additional Info:
OS: [Windows 11]
Holochain version: 0.5.0 --dev 21[Run hc --version hc-cli 0.5.0 --dev 21]
Installed using: [nix develop “github:holochain/holonix?ref=main”]

Question:
Do I need to explicitly expose HTTP routes in my DNA?
How can I check if the app is listening on the correct port?
Any ideas on what might be missing?

#2

Hi @Muzaffar060 , people don’t typically use hc sandbox by itself; they typically use hc spin to generate a sandbox and fire up a UI all in one go. I’m just about to shut down new posts in this forum, but you can head over to the Discord chat (you can find a link in the banner at this site, or go to https://holochain.org and find it in the top header) and ask the question over there.