DCS fails to install with a 1603 error right after trying to install just after installing "Protection\Agent\IPS\bin\EFAInst.exe. SEP is installed and was damaged by the agent cleanup tool or other circumstance.
InstallShield 15:24:12: CallScriptFunctionFromMsiCA() ends MSI (s) (A8:DC) [15:24:12:505]: Executing op: ActionStart(Name=efainst_install.C1599C28_9DB3_446E_AC61_80DD180FF696,Descri ption=Registering with SymEFA.,) Action 15:24:12: efainst_install.C1599C28_9DB3_446E_AC61_80DD180FF696. Registering with SymEFA. MSI (s) (A8:DC) [15:24:12:508]: Executing op: CustomActionSchedule(Action=efainst_install.C1599C28_9DB3_446E_AC61_80DD180F F696,ActionType=3073,Source=BinaryData,Target=EFAInstall,CustomActionData="C :\Program Files (x86)\Symantec\Critical System Protection\Agent\IPS\bin\EFAInst.exe" "SYMEFA-CSP" /install /KeepDriverRunning) MSI (s) (A8:1C) [15:24:12:511]: Invoking remote custom action. DLL: C:\Windows\Installer\MSID45.tmp, Entrypoint: EFAInstall EFAINST_TRACE [15:24:12:549]: --> Starting ValidateCurrentProcess... EFAINST_TRACE [15:24:12:551]: ValidateCurrentProcess (86) - Initializing verify trust... EFAINST_TRACE [15:24:12:552]: ValidateCurrentProcess (103) - Get current process info... EFAINST_TRACE [15:24:12:556]: ValidateCurrentProcess (107) - Check process path... EFAINST_TRACE [15:24:12:557]: ValidateCurrentProcess (127) - Validate process path... EFAINST_TRACE [15:24:12:799]: ValidateCurrentProcess (132) - Verify couldn't successfully validate process id: 2716 for 4 signature. ccVTErrorType = 3 EFAINST_TRACE [15:24:12:800]: <-- ValidateCurrentProcess ended CustomAction efainst_install.C1599C28_9DB3_446E_AC61_80DD180FF696 returned actual error code 1603 (note this may not be 100% accurate if translation happened inside sandbox)
DCS 6.8.1
The below general steps resolve most if not all install issues which result in the MSI Installer 1603 error.