calibre 5.20 won't startup

[sonar liu]

I have installed and reinstalled the Calibre including the previous version again and again. But it won't run. And I searched a lot of measure, however it didn't work. Yesterday I recovered the Windows, it worked. When I restart the Windows, itwas troubled. The protable Calibre can't run either.
The CMD code is
C:\Users\liu>calibre-debug -g
calibre 5.2 [64bit] embedded-python: True is64bit: True
Windows-10-10.0.19041-SP0 Windows ('64bit', 'WindowsPE')
('Windows', '10', '10.0.19041')
Python 3.8.5
Windows: ('10', '10.0.19041', 'SP0', 'Multiprocessor Free')
Interface language: zh_CN
Turning on automatic hidpi scaling
devicePixelRatio: 2.0
logicalDpi: 96.0 x 96.0
physicalDpi: 113.67832167832168 x 113.51955307262568
Using calibre Qt style: True