Troubleshooting Anaconda and Anaconda Navigator Startup

Softhints -

Recently I installed and removed feed packages from my anaconda environment. This resulted into several unexpected errors like:

  • Could not load the Qt platform plugin “xcb” in “” even though it was found
  • Python3: ImportError: /lib/x86_64-linux-gnu/libQt5Core.so.5: version Qt_5.15' not found
  • ImportError: /home/user/anaconda3/lib/python3.12/site-packages/PyQt5/Qt/lib/libQt5Core.so.5: version Qt_5.15' not found (required by /home/user/anaconda3/lib/python3.12/site-packages/PyQt5/QtWebEngineWidgets.abi3.so)
  • anaconda undefined symbol: _ZN15QVulkanInstanceC1Ev, version Qt_5
  • Import error with PyQt5 : undefined symbol:_ZNSt12out_of_rangeC1EPKc,versionQt_5
  • Qt plugin could not load, undefined symbol: _ZN23QPlatformVulkanInstance22presentAboutToBeQueuedEP7QWindow

More errors like:

 WARNING linux_scaling.get_scaling_factor_using_dbus:39
Can't detect system scaling factor settings for primary monitor.

qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Environment

My environment is:

  • Linux Mint 22 Cinnamon
  • anaconda-navigator=2.6.4
  • python 3.12

Solution - downgraded version of pyqt5 using pip

I spent several hours and tested multiple solutions. The only one which has worked in my case was the one below:

pip install pyqt5==5.14.2
pip install pyqtwebengine==5.14

Updating the anaconda navigator resulted into more errors which I solve by:

pip install --upgrade pyqt5==5.15.0

Finally there were few spyder compatibility issues:

pip install --upgrade pyqtwebengine==5.15.0

Troubleshooting Anaconda Startup

For troubleshouting anaconda and anaconda navigator I recommend you to try to:

For example you can check the following error: “Could not load the Qt platform plugin “xcb” in “” even though it was found” error in the official troubleshouting guide:

“Could not load the Qt platform plugin “xcb” in “” even though it was found” error

or find this topic from the community: Error opening anaconda navigator

Recovering your Anaconda installation

Finally you may try to fix your anaconda installation by following the steps described into:

Recovering your Anaconda installation

Resources