[FIXED] Spyder launch error in brand new conda environment

Issue

I just created a brand new environment in conda, and spyder won't launch (from terminal or anaconda) with the following error:

Traceback (most recent call last):
File "/Users/alexanderniewiarowski/anaconda3/envs/fenics2018/lib/python3.6/site-packages/qtpy/QtWebEngineWidgets.py", line 22, in 
from PyQt5.QtWebEngineWidgets import QWebEnginePage
ImportError: dlopen(/Users/alexanderniewiarowski/anaconda3/envs/fenics2018/lib/python3.6/site-packages/PyQt5/QtWebEngineWidgets.so, 2): Library not loaded: @rpath/libQt5WebEngineWidgets.5.dylib
Referenced from: /Users/alexanderniewiarowski/anaconda3/envs/fenics2018/lib/python3.6/site-packages/PyQt5/QtWebEngineWidgets.so
Reason: image not found

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/Users/alexanderniewiarowski/anaconda3/envs/fenics2018/bin/spyder", line 11, in 
sys.exit(main())
File "/Users/alexanderniewiarowski/anaconda3/envs/fenics2018/lib/python3.6/site-packages/spyder/app/start.py", line 179, in main
from spyder.app import mainwindow
File "/Users/alexanderniewiarowski/anaconda3/envs/fenics2018/lib/python3.6/site-packages/spyder/app/mainwindow.py", line 92, in 
from qtpy import QtWebEngineWidgets # analysis:ignore
File "/Users/alexanderniewiarowski/anaconda3/envs/fenics2018/lib/python3.6/site-packages/qtpy/QtWebEngineWidgets.py", line 26, in 
from PyQt5.QtWebKitWidgets import QWebPage as QWebEnginePage
ModuleNotFoundError: No module named 'PyQt5.QtWebKitWidgets'

Similar questions have been asked here, but the error is different. This is my config. I have the most recent version of PyQt.

     active environment : fenics2018
    active env location : /Users/alexanderniewiarowski/anaconda3/envs/fenics2018
            shell level : 1
       user config file : /Users/alexanderniewiarowski/.condarc
 populated config files : /Users/alexanderniewiarowski/.condarc
          conda version : 4.5.9
    conda-build version : 3.4.1
         python version : 3.6.4.final.0
       base environment : /Users/alexanderniewiarowski/anaconda3  (writable)
           channel URLs : https://conda.anaconda.org/conda-forge/osx-64
                          https://conda.anaconda.org/conda-forge/noarch
                          https://repo.anaconda.com/pkgs/main/osx-64
                          https://repo.anaconda.com/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/free/osx-64
                          https://repo.anaconda.com/pkgs/free/noarch
                          https://repo.anaconda.com/pkgs/r/osx-64
                          https://repo.anaconda.com/pkgs/r/noarch
                          https://repo.anaconda.com/pkgs/pro/osx-64
                          https://repo.anaconda.com/pkgs/pro/noarch
          package cache : /Users/alexanderniewiarowski/anaconda3/pkgs
                          /Users/alexanderniewiarowski/.conda/pkgs
       envs directories : /Users/alexanderniewiarowski/anaconda3/envs
                          /Users/alexanderniewiarowski/.conda/envs
               platform : osx-64
             user-agent : conda/4.5.9 requests/2.18.4 CPython/3.6.4 Darwin/17.7.0 OSX/10.13.6
                UID:GID : 501:20
             netrc file : None
           offline mode : False

Solution

Not sure what was the source of the problem but spyder --reset fixed it.

Answered By - olekN