If you're seeing "Code interpreter session expired" in ChatGPT, your session timed out and the files you uploaded or generated are gone. This is one of the most frustrating limitations of ChatGPT's code interpreter—and there's no real fix, only workarounds.
Why This Happens
ChatGPT's code interpreter runs in a sandboxed environment that resets automatically. Your session expires when:
Inactivity timeout: After roughly 10-60 minutes of no interaction, the session is recycled
Server-side resets: OpenAI periodically clears sessions for resource management
Download links expire: Even if you generated a file, the download link stops working after the session ends
The core problem: ChatGPT doesn't have persistent storage. Every code interpreter session is temporary by design.
Quick Recovery Steps
If you just hit this error and need your work back:
Re-upload source files: If you uploaded data, you'll need to upload it again
Ask ChatGPT to regenerate: Say "Please regenerate the file you just created" — this sometimes works if the session hasn't fully cleared
Copy code to local: If ChatGPT showed you Python code, copy it and run locally before asking for output files
For future sessions:
Download generated files immediately — don't leave tabs open
Copy any code ChatGPT writes before requesting file exports
For long analysis tasks, break work into smaller chunks and save outputs between steps
The Underlying Limitation
The "code interpreter session expired" problem points to a deeper architectural constraint: ChatGPT wasn't designed for persistent work. It's optimized for conversation, not computation that spans sessions.
If you're using code interpreter for serious data analysis, file processing, or any workflow that takes more than a few minutes, you'll keep hitting this wall.
A Better Architecture: Persistent AI with Your Own Server
The session expiration problem disappears when your AI has access to a real filesystem. On Zo Computer, your AI assistant runs on a persistent Linux server where:
Files don't disappear: Your workspace is a real filesystem that survives sessions
Code runs in a real environment: Python, Node, and any language you need—with your packages installed
No timeout limits: Long-running jobs complete in the background
Full tool access: SSH, databases, APIs, browser automation—not just a sandbox
When you ask Zo to analyze a CSV, generate a report, or transform data, the output lives in your filesystem. Come back tomorrow and it's still there.
Example: Data Analysis That Persists
On ChatGPT code interpreter, you might say:
"Analyze this sales data and create a summary report"
Then race to download the output before the session expires.
On Zo, the same workflow:
"Analyze this sales data in my workspace and save the report to Reports/sales-summary.md"
The file exists on your server. You can revisit it, share it, or reference it in future conversations. The AI remembers where things are because they're actually stored somewhere real.
When to Use What
Use ChatGPT code interpreter for:
Quick one-off calculations
Exploratory data analysis you don't need to save
Simple file conversions where you can download immediately
Use a persistent environment for:
Multi-step analysis workflows
Files you need to reference across sessions
Automation that runs on a schedule
Any work where "session expired" would cost you hours
The code interpreter session expiration error isn't a bug—it's a fundamental design tradeoff. If you're hitting it repeatedly, you've outgrown the tool's intended use case.