The 32bit client works fine.

Only the 64bit client has something wrong. I searched and read some old threads, deleting the dndclient64.exe and let launcher re-download file didn't work.

I checked the dndclient64.log file, it reads:
Code:
000000000.000: Initializing client - build version is [5801.0051.4888.4003.RELEASE] 
000000000.000: Initializing the global event handler...
000000000.000: Creating trigger schedulers...
000000000.000: Initializing the network...
000000000.000: Initializing the cache...
000000000.000: CLCache::Init: called.
000000000.000: LookForFile trying cwd
000000000.000: Is_File_Here found 'client_general.dat' in 'E:/Games/Dungeons & Dragons Online'
000000000.000: 

DiskCon::InitFile:
  datfile "client_general.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_highres.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_highres_aux_1.datx" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile: Warning: datfile "client_highres_aux_1.datx" did not contain any GUID version stamp information!

000000000.000: 

DiskCon::InitFile:
  datfile "client_gamelogic.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_anim.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_mesh.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_sound.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_surface.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_1.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_1.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_2.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_2.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_3.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_3.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_4.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_4.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_local_English.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: Initializing display with title 'Dungeons and Dragons Online'...
000000000.000: Device_WIN32::Init: called.
000000000.000: Device_WIN32::InitTimer resolution successfully set to [1].
000000000.000: Device_WIN32::InitDEVICE|  Detected operating system: Windows 7
000000000.000: Device_WIN32::Cleanup: called.
IDK why it detected the OS is Windows 7, but this seems not to be the root cause. The game called a Cleanup operation, and the initializing process just stopped here.

Lucky there is an old log file (created in Mar 30), it was a successful initialization, and it reads:
Code:
000000000.000: Initializing client - build version is [5801.0051.4888.4003.RELEASE] 
000000000.000: Initializing the global event handler...
000000000.000: Creating trigger schedulers...
000000000.000: Initializing the network...
000000000.000: Initializing the cache...
000000000.000: CLCache::Init: called.
000000000.000: LookForFile trying cwd
000000000.000: Is_File_Here found 'client_general.dat' in 'E:/Games/Dungeons & Dragons Online'
000000000.000: 

DiskCon::InitFile:
  datfile "client_general.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_highres.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_highres_aux_1.datx" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile: Warning: datfile "client_highres_aux_1.datx" did not contain any GUID version stamp information!

000000000.000: 

DiskCon::InitFile:
  datfile "client_gamelogic.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_anim.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_mesh.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_sound.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_surface.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_1.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_1.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_2.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_2.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_3.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_3.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_cell_4.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_map_4.dat" stamped with datpack versions eng:112, game:0,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: 

DiskCon::InitFile:
  datfile "client_local_English.dat" stamped with datpack versions eng:112, game:3,
  executable supporting datpack versions eng:-1, game: -1.

000000000.000: Initializing display with title 'Dungeons and Dragons Online'...
000000000.000: Device_WIN32::Init: called.
000000000.000: Device_WIN32::InitTimer resolution successfully set to [1].
000000000.000: Device_WIN32::InitDEVICE|  Detected operating system: Windows 7
000000000.000: DEVICE|  Starting up the graphics engine...
000000000.000: Initializing the smartbox...
000000000.000: Initializing the user interface...
000000000.000: Client ready
000000004.341: Client::Connect() async logon begun.
...
...
After the game detected my OS, it started graphics engine/UI/logon and so on.

My computer is OMEN 17, 12700H+3070. And here is PC/OS info:
CPU 12th Gen Intel(R) Core(TM) i7-12700H 2.30 GHz
RAM 64.0 GB
OS Windows 11 Professional
Version 22H2
Version 22621.1413

I'm not willing to re-download the whole game, since it takes too long time. Can any dev trouble-shooting this issue please?
Thank you.