Troubleshooting
Fix common problems with starting DemoVexa, connecting Claude and ElevenLabs, folder access, builds, renders and batches.
This page lists the problems people run into most, grouped by what you see, with the exact message DemoVexa shows and how to fix it. Start with Settings: its checks catch most problems and show the fix, often with a command you can copy.
Tip
Open Settings (⌘ ,, on Windows/Linux Ctrl ,) and click Check again. A failing check shows what's wrong and, where it helps, a command with Copy. Run it in Terminal or PowerShell, then check again.
#DemoVexa won't start
"Node.js is not installed (need 20.9 or newer)."
Install Node.js 20.9 or newer, then run the launcher again.
# macOS (Homebrew)
brew install node
# macOS or Linux, with nvm
nvm install 22
# Windows
winget install OpenJS.NodeJS.LTS
"Database migrations failed. Check that studio/storage is writable."
DemoVexa couldn't set up its database. Make sure the data folder (by default studio/storage in the DemoVexa folder) is writable by your user and that the disk isn't full, then run the launcher again. See Folders and permissions.
"Build failed; starting in dev mode instead."
The launcher couldn't rebuild the app after an update, so it started in a slower development mode. DemoVexa still works. Run the launcher again later; if the message keeps appearing, contact support with the launcher's output.
"The studio didn't stop in 10 seconds; forcing it."
DemoVexa was slow to stop, so the launcher stopped it. You don't need to do anything.
The port is busy
If another program is using DemoVexa's address (http://localhost:1557), quit that program and run the launcher again. If it's DemoVexa itself, the launcher says "The studio is already running … Opening it." and opens it.
#Database
Database check: "Can't open"
Check that the data folder is writable in Settings → Folder access, then restart DemoVexa.
"Migrations: X of Y applied"
Restart DemoVexa with the launcher. It applies the missing migrations as it starts.
#Missing tools and packages
Git isn't installed
DemoVexa uses Git to read your app's history for Ideas.
# macOS
xcode-select --install
# Linux (Ubuntu/Debian)
sudo apt install git
# Windows
winget install Git.Git
A packages check fails
Settings → Rendering checks the packages DemoVexa needs. If one fails, copy the npm install command it shows and run it in the folder it names.
#Claude
"Claude Code CLI not found…"
You're using My Claude login, but DemoVexa can't find Claude Code. Install it and sign in:
# macOS or Linux
curl -fsSL https://claude.ai/install.sh | bash && claude
# Windows (PowerShell)
irm https://claude.ai/install.ps1 | iex; claude
If Claude Code is installed somewhere unusual, set CLAUDE_CLI_PATH to its full path.
"No Anthropic API key…"
You're using Anthropic API key mode without a key. Add one in Settings → Claude, or switch How Claude runs to My Claude login.
"The key was rejected: it's wrong, revoked or for another account."
Copy the key again from your Anthropic account and replace it in Settings → Claude.
"The account is out of credit or over its rate limit."
Add credit to your Anthropic account, or wait for the rate limit to pass, then click Test connection.
"That doesn't look like an Anthropic API key (they start with sk-ant-)."
You may have pasted a different key. Anthropic API keys start with sk-ant-.
"The key has spaces or line breaks in it; copy it again."
Copy the key again, without spaces or line breaks.
"Claude's usage limit was reached. Trying again at HH:MM (wait N of 8)."
Shown during a build. You don't need to do anything: the build waits and tries again every 15 minutes, for up to 2 hours. See Animate.
#ElevenLabs
"ElevenLabs didn't accept the key."
Copy the key again from your ElevenLabs account and replace it in Settings → ElevenLabs.
"That looks too short for an ElevenLabs API key."
Part of the key is missing. Copy the whole key again.
"Your ElevenLabs plan has no free voice slots. Remove a voice on elevenlabs.io (My Voices) or upgrade, then try again."
Adding a voice from the Voice Library needs a free slot on your ElevenLabs account. Remove a voice you don't use on elevenlabs.io, under My Voices, or upgrade your ElevenLabs plan.
#Folders and permissions
"Use the full path, e.g. /Users/you/code/app or C:\code\app (or click Choose folder)."
Paste the folder's full path, or click Choose folder… and pick it.
"That folder doesn't exist on this computer."
Check the path for typos, or use Choose folder….
A Folder access check fails
Settings → Folder access tests that DemoVexa can write, read and delete in its folders. If one fails:
| System | What to check |
|---|---|
| macOS | System Settings → Privacy & Security → Files and Folders, or Full Disk Access, for the app you start DemoVexa from (such as Terminal) |
| Windows | The folder's Security permissions, and Controlled folder access in Windows Security |
| Linux | Ownership of the folder (see below) |
On Linux, make your user the owner of the folder:
sudo chown -R "$USER" "<dir>"
Also check that the disk isn't full and the drive isn't read-only.
The website import doesn't work
Import → From the website needs a website that is public and reachable. Sites behind a login or on a private network can't be imported; add your logo, colours and fonts by hand instead.
#Builds
"Stopped unexpectedly (the studio was closed or the worker crashed). Start it again."
The build was cut off. Click Restart on the project, or Restart all from Needs attention on the Projects page.
"Build failed"
Open the project's Animate step and choose Retry, Rebuild from scratch or Ask Claude. See If the build fails.
#Renders
"Could not find composition …Reel"
That format wasn't built. Go to the Export step and click Ask Claude to add it next to the format, then render again.
"Render failed (N formats)"
Click Restart on the project card. If it fails again, check Settings → Rendering for a failing check, such as Chrome Headless Shell or FFmpeg.
The first render takes longer
Chrome Headless Shell downloads on your first render. To fetch it yourself, run:
npx remotion browser ensure
#Batches
A batch didn't run overnight
The computer went to sleep. DemoVexa keeps the computer awake while a batch runs, but a closed laptop lid still puts it to sleep. Leave the lid open and check your sleep settings.
An item in a batch failed or was stopped
Click Retry on the item in the batch card. Projects stopped by a shutdown can also be restarted from Needs attention → Restart all on the Projects page.
#Linux
"error while loading shared libraries"
Chrome needs some system libraries to render. Install the Chrome libraries (including libnss3 and libcups2), then render again. Settings → Rendering lists what's missing.
The folder picker doesn't open
Install zenity (or kdialog):
sudo apt install zenity
#Logs
DemoVexa writes its logs to the logs folder inside the data folder, by default studio/storage/logs/. Include them when you contact support.
#Related
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