Q. How can I only perform an action in a batch file if a file doesn't exist?

A. Leading on from my previous FAQ about installing based on architecture version, the next requirement was to only install the agent if it weren't already installed. This can be achieved in a number of ways, but the easiest was to just look for the DPM client user interface executable and, if found, skip the entire batch file.

To do this, just use

if exist  goto :

If you want to do something if a file doesn't exist, use

if not exist  goto :

My updated agent installation script became:

@echo off
 echo Checking for DPM agent
 if exist "C:Program FilesMicrosoft Data Protection ManagerDPMbinDPMClientUI.exe" goto EXIT

 echo Detecting OS processor type

 if "%PROCESSOR_ARCHITECTURE%"=="AMD64" goto 64BIT
 echo 32-bit OS
 \savdaldpm01ProtectionAgentsRA3.0.7558.0i386DPMAgentInstaller_x86 /q
 goto SETSERV

 :64BIT
 echo 64-bit OS
 \savdaldpm01ProtectionAgentsRA3.0.7558.0amd64DPMAgentInstaller_x64 /q 

 :SETSERV
 "C:Program FilesMicrosoft Data Protection ManagerDPMbinsetdpmserver.exe" -dpmservername savdaldpm01.savilltech.net

 :EXIT