Can't launch Spyder - 'Invalid file descriptor to ICU data received'

Question

I can't run Spyder from windows shortcut. It doesn't open at all. After that I tried running it from Anaconda navigator which shows the following errors. I have uninstalled the Spyder and reinstalled it also. It happened after tried installing Opencv in Anaconda.

[1205/235251.482:ERROR:icu_util.cc(178)] Invalid file descriptor to ICU data received.
[1205/235251.483:FATAL:icu_util.cc(297)] Check failed: result. 
Backtrace:
GetHandleVerifier [0x00007FFA2A88D261+125633]
QWebEngineUrlSchemeHandler::qt_static_metacall [0x00007FFA2A822E63+5555]
GetHandleVerifier [0x00007FFA2AB7A3B5+3193877]
QtWebEngineCore::AuthenticationDialogController::qt_static_metacall [0x00007FFA2A8026F5+7629589]
QtWebEngineCore::WebContentsAdapter::webContents [0x00007FFA2A0A8351+20433]
QtWebEngineCore::WebContentsAdapter::webContents [0x00007FFA2A0A89BE+22078]
QtWebEngineCore::WebContentsAdapter::WebContentsAdapter [0x00007FFA2A09C038+56]
QWebEngineHistoryItem::url [0x00007FFA55253547+423]
QWebEnginePage::QWebEnginePage [0x00007FFA55253893+147]
QWebEnginePage::QWebEnginePage [0x00007FFA552537DD+45]
(No symbol) [0x00007FFA5C9483C4]
(No symbol) [0x00007FFA756313BF]
type_call [0x00007FFA5364F8A7+167] (c:\ci\python_1572550317365\work\objects\typeobject.c:972)
_PyObject_FastCallKeywords [0x00007FFA5364F63A+378] (c:\ci\python_1572550317365\work\objects\call.c:199)
call_function [0x00007FFA53657709+1017] (c:\ci\python_1572550317365\work\python\ceval.c:4619)
_PyEval_EvalFrameDefault [0x00007FFA53657CEF+1199] (c:\ci\python_1572550317365\work\python\ceval.c:3125)
_PyFunction_FastCallDict [0x00007FFA53640C9D+221] (c:\ci\python_1572550317365\work\objects\call.c:322)
slot_tp_init [0x00007FFA5363EDF3+315] (c:\ci\python_1572550317365\work\objects\typeobject.c:6636)
type_call [0x00007FFA5364F8A7+167] (c:\ci\python_1572550317365\work\objects\typeobject.c:972)
_PyObject_FastCallKeywords [0x00007FFA5364F63A+378] (c:\ci\python_1572550317365\work\objects\call.c:199)
call_function [0x00007FFA53657709+1017] (c:\ci\python_1572550317365\work\python\ceval.c:4619)
_PyEval_EvalFrameDefault [0x00007FFA53657CEF+1199] (c:\ci\python_1572550317365\work\python\ceval.c:3125)
_PyFunction_FastCallDict [0x00007FFA53640C9D+221] (c:\ci\python_1572550317365\work\objects\call.c:322)
slot_tp_init [0x00007FFA5363EDF3+315] (c:\ci\python_1572550317365\work\objects\typeobject.c:6636)
type_call [0x00007FFA5364F8A7+167] (c:\ci\python_1572550317365\work\objects\typeobject.c:972)
_PyObject_FastCallKeywords [0x00007FFA5364F63A+378] (c:\ci\python_1572550317365\work\objects\call.c:199)
call_function [0x00007FFA53657709+1017] (c:\ci\python_1572550317365\work\python\ceval.c:4619)
_PyEval_EvalFrameDefault [0x00007FFA53657CEF+1199] (c:\ci\python_1572550317365\work\python\ceval.c:3125)
_PyFunction_FastCallDict [0x00007FFA53640C9D+221] (c:\ci\python_1572550317365\work\objects\call.c:322)
slot_tp_init [0x00007FFA5363EDF3+315] (c:\ci\python_1572550317365\work\objects\typeobject.c:6636)
type_call [0x00007FFA5364F8A7+167] (c:\ci\python_1572550317365\work\objects\typeobject.c:972)
_PyObject_FastCallKeywords [0x00007FFA5364F63A+378] (c:\ci\python_1572550317365\work\python\pythonrun.c:432)
PyRun_AnyFileExFlags [0x00007FFA537B513B+99] (c:\ci\python_1572550317365\work\python\pythonrun.c:85)
pymain_run_file [0x00007FFA5370137B+191] (c:\ci\python_1572550317365\work\modules\main.c:433)
pymain_run_filename [0x00007FFA53701423+111] (c:\ci\python_1572550317365\work\modules\main.c:1613)
pymain_run_python [0x00007FFA53670A24+390720] (c:\ci\python_1572550317365\work\modules\main.c:2873)
pymain_main [0x00007FFA536113A5+41] (c:\ci\python_1572550317365\work\modules\main.c:3415)
Py_Main [0x00007FFA53611052+82] (c:\ci\python_1572550317365\work\modules\main.c:3437)

Answer 1

I ran into this same error when opening Spyder via the command line using spyder --debug-info verbose.

The fix was actually quite simple, based on the recommendation here.

Point 3:

Ensure the presence icudtl.dat file inside application directory

Simply copying icudtl.dat fixed the issue.

• From: /c/anaconda3/envs/py37/Library/resources/icudtl.dat
• To: /c/anaconda3/envs/py37/

Upstream Fix

Before receiving this error, I received an error stating: Could not find QtWebEngineProcess.exe

The fix for this was based on this recommendation.

Copying the following files to C:\Python36 (python's root folder) seems to be a workaround

C:\Python36\qtwebengine_devtools_resources.pak
C:\Python36\qtwebengine_resources.pak
C:\Python36\qtwebengine_resources_100p.pak
C:\Python36\qtwebengine_resources_200p.pak
C:\Python36\QtWebEngineProcess.exe

Answer 2

Actually, instead of copying the files to the Python root directory you should check the qt.conf file in the Python root directory whether it links to the correct subdirectories (cf. the answer here). If you get the error messages they are most likely wrong.