❗️ Common Installation Issues

This is a list of possible issues that you may encounter when installing Langflow and how to solve them.


_10> No module named 'langflow.__main__'

Run python -m langflow run instead of langflow run.
If that doesn't work, reinstall Langflow with _python -m pip install langflow --pre -U.
If that doesn't work, reinstall Langflow and its dependencies with python -m pip install langflow --pre -U --force-reinstall.

When you try to run Langflow using the command langflow run, you may encounter the following error:


_10> langflow runTraceback (most recent call last): File ".../langflow", line 5, in <module>  from langflow.__main__ import mainModuleNotFoundError: No module named 'langflow.__main__'

There are two possible reasons for this error:

You've installed Langflow using pip install langflow but you already had a previous version of Langflow installed in your system. In this case, you might be running the wrong executable. To solve this issue, run the correct executable by running python -m langflow run instead of langflow run. If that doesn't work, try uninstalling and reinstalling Langflow with python -m pip install langflow --pre -U.
Some version conflicts might have occurred during the installation process. Run python -m pip install langflow --pre -U --force-reinstall to reinstall Langflow and its dependencies.


_10> Something went wrong running migrations. Please, run 'langflow migration --fix'

Clear the cache by deleting the contents of the cache folder.

This folder can be found at:

Linux or WSL2 on Windows: home/<username>/.cache/langflow/
MacOS: /Users/<username>/Library/Caches/langflow/

This error can occur during Langflow upgrades when the new version can't override langflow-pre.db in .cache/langflow/. Clearing the cache removes this file but will also erase your settings.

If you wish to retain your files, back them up before clearing the folder.