Em Client No Longer Opens (libcef.dll)

1

I am no longer able to open Em Client – it won’t even display the Em Client splash screen.

When I attempt to open Em Client, “Event ID 1000 - Application Error” is logged in Windows Event Viewer.

It appears MailClient.exe is trying to use libcef.dll (Chromium Embedded Framework (CEF) Dynamic Link Library), but it crashes due to an exception (0x4000001f). I’m also not sure why it’s so old (Chromium 73, when the current stable version of Chromium is 125).

Message     : Faulting application name: MailClient.exe, version: 9.2.2258.0, time stamp: 0x65fc6f47
              Faulting module name: libcef.dll, version: 73.0.0.0, time stamp: 0x5c8499d0
              Exception code: 0x4000001f
              Fault offset: 0x01a37cd5
              Faulting process ID: 0x1eb8
              Faulting application start time: 0x01daaa30e920f4cf
              Faulting application path: C:\Program Files (x86)\eM Client\MailClient.exe
              Faulting module path: C:\Program Files (x86)\eM Client\libcef\libcef.dll
              Faulting package full name:
              Faulting package-relative application ID:
Id          : 1000

libcef.dll hash:

Algorithm : SHA256
Hash      : F3514D3AE4555E99A42A8B2D75D5533DE4D0135CAFEC6D03807E5CA5FB87E576
Path      : C:\Program Files (x86)\eM Client\libcef\libcef.dll

https://www.virustotal.com/gui/file/f3514d3ae4555e99a42a8b2d75d5533de4d0135cafec6d03807e5ca5fb87e576/details

Em Client: 9.2.2258 (msi installer)
Windows 11 23H2 (22631.3593)

2

Issue happened again, this time with eM Client 10.1.4828.0.

I restarted the laptop using [Start Menu > Power > Restart] and when the machine restarted eM Client would no longer launch.

The same “Event ID 1000 - Application Error” is logged in Windows Event Viewer, with the same exception code. EM Client is also still using the same out-of-date Chromium Embedded Framework (CEF) Dynamic Link Library (using 73.0.0.0 – when the current stable version of Chromium is 131.0.6778.86).

Message     : Faulting application name: MailClient.exe, version: 10.1.4828.0, time stamp: 0x67110000
              Faulting module name: libcef.dll, version: 73.0.0.0, time stamp: 0x5c8499d0
              Exception code: 0x4000001f
              Fault offset: 0x01a37cd5
              Faulting process id: 0x0x2040
              Faulting application start time: 0x0x1DB471610807989
              Faulting application path: C:\Program Files (x86)\eM Client\MailClient.exe
              Faulting module path: C:\Program Files (x86)\eM Client\libcef\libcef.dll
              Faulting package full name:
              Faulting package-relative application ID:
Id          : 1000

The only “fix” is to completely uninstall and reinstall eM Client.

Em Client: 10.1.4828.0 (msi installer)
Windows 11 23H2 (22631.4460)

3

Have a look at this thread which may help, even though you said reinstall of eM Client fixed it