The Python backend used inside ChatGPT is intermittently failing to execute file operations, even though the code executes without syntax issues. Functionality that previously worked reliably — including reading/writing JSON, creating backups, and performing atomic file replacement — now regularly fails with no clear error message.
Symptoms
-
Python tool frequently returns the message:
“The Python code did not successfully execute” -
The backend fails to write files, copy files, or perform
os.replace(...)even though identical code worked for months. -
There is no actual Python traceback, leaving the user with no actionable debugging information.
-
Failures occur even with very small and simple file operations (JSON dump, text write, backup copy, etc.).
What Used to Work
Until recently, the Python sandbox handled file operations reliably, including:
-
Writing JSON files
-
Creating temporary files and atomically replacing originals
-
Copying files using
shutil.copy2 -
Using file paths under
/mnt/data/without errors -
Running multi-step operations within a single Python exec
All of these operated consistently without intermittent failures.
What Happens Now
Even simple operations like:
with open("/mnt/data/test.json", "w") as f:
json.dump({"ok": True}, f)
can fail with the generic message above, and no file is created.
Likewise, common tasks such as:
-
shutil.copy2(...) -
os.replace(...) -
Writing temp files (
/mnt/data/*.tmp) -
Reading immediately after writing
may fail silently or produce the “did not successfully execute” message.
Anyone else have GPT’s now not working since the 5.1 push?






