pgAdmin 4 not starting after upgrade to 6.4

Hi all,

After upgrading from 6.2 to 6.4, when I start pgAdmin I get an

"The pgAdmin 4 server could not be contacted"

message, with the environment details shown below.

I have tried re-installing pgadmin4-6.4-x64.exe, and tried rebooting
windows.

Should I uninstall some component and reinstall? Or? And if you need any
logs, please let me know where to grab them.

Thanks,
Dave

pgAdmin Runtime Environment
--------------------------------------------------------
Python Path: "C:\Users\User\AppData\Local\Programs\pgAdmin
4\v6\python\python.exe"
Runtime Config File:
"C:\Users\User\AppData\Roaming\pgadmin\runtime_config.json"
pgAdmin Config File: "C:\Users\User\AppData\Local\Programs\pgAdmin
4\v6\web\config.py"
Webapp Path: "C:\Users\User\AppData\Local\Programs\pgAdmin
4\v6\web\pgAdmin4.py"
pgAdmin Command: "C:\Users\User\AppData\Local\Programs\pgAdmin
4\v6\python\python.exe -s C:\Users\User\AppData\Local\Programs\pgAdmin
4\v6\web\pgAdmin4.py"
Environment:
- ALLUSERSPROFILE: C:\ProgramData
- APPDATA: C:\Users\User\AppData\Roaming
- CHROME_CRASHPAD_PIPE_NAME: \\.\pipe\crashpad_1836_DIKKTZARVGRVNIBP
- CHROME_RESTART: NW.js|Whoa! NW.js has crashed. Relaunch
now?|LEFT_TO_RIGHT
- CommonProgramFiles: C:\Program Files\Common Files
- CommonProgramFiles(x86): C:\Program Files (x86)\Common Files
- CommonProgramW6432: C:\Program Files\Common Files
- COMPUTERNAME: USER-PC
- ComSpec: C:\Windows\system32\cmd.exe
- FP_NO_HOST_CHECK: NO
- HOMEDRIVE: C:
- HOMEPATH: \Users\User
- JAVA_HOME: C:\Program Files\Java\jdk1.8.0_271
- LOCALAPPDATA: C:\Users\User\AppData\Local
- LOGONSERVER: \\USER-PC
- NUMBER_OF_PROCESSORS: 4
- OS: Windows_NT
- Path: C:\Program Files (x86)\Common
Files\Oracle\Java\javapath;"C:\Program Files
(x86)\Java\jre7\bin";C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program
Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program
Files\PuTTY\;C:\Program Files\Git\cmd
- PATHEXT: .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
- PGADMIN_INT_KEY: d02a954c-b93a-445b-b57b-ff2764541239
- PGADMIN_INT_PORT: 61303
- PGADMIN_SERVER_MODE: OFF
- PROCESSOR_ARCHITECTURE: AMD64
- PROCESSOR_IDENTIFIER: Intel64 Family 6 Model 58 Stepping 9, GenuineIntel
- PROCESSOR_LEVEL: 6
- PROCESSOR_REVISION: 3a09
- ProgramData: C:\ProgramData
- ProgramFiles: C:\Program Files
- ProgramFiles(x86): C:\Program Files (x86)
- ProgramW6432: C:\Program Files
- PSModulePath: C:\Windows\system32\WindowsPowerShell\v1.0\Modules\
- PUBLIC: C:\Users\Public
- SESSIONNAME: Console
- SystemDrive: C:
- SystemRoot: C:\Windows
- TEMP: C:\Users\User\AppData\Local\Temp
- TMP: C:\Users\User\AppData\Local\Temp
- USERDOMAIN: User-PC
- USERNAME: User
- USERPROFILE: C:\Users\User
- windir: C:\Windows
- windows_tracing_flags: 3
- windows_tracing_logfile: C:\BVTBin\Tests\installpackage\csilogfile.log
--------------------------------------------------------

Cheers,
Dave