Unable to open coregistration GUI

Dear colleagues,

I’m having trouble using the MNE-Python coregistration GUI. There appears to be a problem with the GUI backend, which I’ve been unable to solve. When running the command mne coreg, I get the following warning:
/user/anaconda3/bin/mne:8: RuntimeWarning: Using the currently selected Pyface backend null is not recommended, and it might not work properly. We recommend using 'qt4' which can be enabled by installing the PyQt5package. sys.exit(main()).
This is followed by an error traceback, ending with File "/user/.local/lib/python3.8/site-packages/pyface/base_toolkit.py", line 190, in __init__ raise NotImplementedError(msg % (toolkit, package, name)) NotImplementedError: the null pyface.ui.null backend doesn't implement message_dialog:MessageDialog.

So, there appears to be an issue with pyface, and the suggested solution is to use Qt instead. However, I wasn’t able to figure out how to change the backend. Any suggestions are welcome. I’m using the latest version of MNE-Python (0.23) on Ubuntu 20.04.


Hello @ruuskas and welcome to the forum!

MNE-Python depends on numerous packages, and getting 3D plotting to work properly is not always a trivial task. Please follow our official installation instructions to create a dedicated MNE-Python environment that will work.

Best wishes,


1 Like

Hello David,

This issue has since been resolved. This was a case of incompatible dependencies, hence the NotImplementedError.


I have flagged @davidbillg’s post as off-topic. Please don’t copy & paste huge chunks of only marginally relevant information. Thank you.