It's actually simple as 1, 2, 3... ;\)
1. copy the install media to a shared folder. Create a BAT file there that will start the installation in unattended mode.
2. Create a bat file on the remote computer that maps a drive to your install share and runs the installation bat file.
3. Create and execute a scheduled task on the remote computer that runs the above bat file

The bat file to install the application is up to you.. it is installed in the folder on the network share with the application setup files.

The bat file to map to the share and run the install file (RmtInst.bat) would be something like this:
 Code:
@Echo Off
Rem Map a drive - define your server and share
Net Use Y: \\server\install_share
y:
REM CD to the folder where the app is stored
CD \AppFolder
REM Run the install bat file you created in step 1
Call MySetup.BAT
This must be copied to the workstation, possibly the C:\TEMP folder. DO NOT use %TEMP% as it is unique per user. THIS PART can be triggered by the login script - code to determine if the required app is missing or outdated can be run by the users even without admin access. They can also copy the local script to the C:\Temp folder.

At this point, I usually write a file to a share somewhere with the workstation name in it. A process running on that server finds the file, extracts the computer name, and performs the following script to run the installation with elevated rights:
 Code:
Break On
; load the tcLib UDF Library
Call 'C:\UDF_Library\tclib.kxf'


; NOTE: The name of the target computer has been extracted from the file or
; otherwise provided in the $Target variable!!


tcInit()                      ; init the library

; Define the APPlication to run, a CoMmenT, and enable the Delete When Done option
$RV = tcDefineTask(“APP=C:\Temp\RmtInst.bat CMT=Remote Installer DWD=1”)

; Define the user account and password to run the task with
$RV = tcDefineTask (“USR=username PWD=password”)

; Save the task to the remote computer using the AppInstall task name
$RV = tcSetEvent($Target, 'AppInstall')

; Run the task created above immediately
$RV = tcExecute($Target, 'AppInstall')
So, in just a few lines, you can create a remote task and execute it with whatever credentials you wish. We have a product that employs this basic methodology, and installations can be triggered by the login script and executed within seconds.

Unless you specify credentials (clear text) to PSExec, you can't use network resources. Installing software via the SYSTEM account isn't a good idea either.

Glenn
_________________________
Actually I am a Rocket Scientist! \:D