This is for Version 5 (newest as of August 2019). Felt silly once I figured this out
Download latest version: https://www.efax.com/efax-help-center/efax-messenger/download-efax-messenger
Run the .exe with a "/qn" switch. I had no luck using the "/extract" command, but once thoroughly reading the /? help window I noticed you can just pass msi switches directly
efaxmessengersetup-5-0-0-50.exe /qn
problem with the command lines are additional users on the same computer, won't see the shortcuts nor able to run the program. so i took the files and build an msi, without any registry keys. three registry lines are needed per user in order to fix the "A required resource was unavailable" error.
REGEDIT4
[HKEY_CURRENT_USER\Software\j2 Global\eFax Messenger 4.4\J2GSDK]
"InstallAppID"="{DF6DA606-904D-4C18-823F-A4CFC3035E53}"
[HKEY_CURRENT_USER\Software\j2 Global\eFax Messenger 4.4\J2GSDK]
"InstallVersionNew"="4.4"
[HKEY_CURRENT_USER\Software\j2 Global\eFax Messenger 4.4\J2GSDK]
"UserInstallTime"=hex:b7,f5,db,4f,
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