This is my absolute last reply for now. .

Just a 'junior member' but try this. . . or I may be able to help further with the actual script. . .Its something I have been wanting to try for a long time. Here is the concept.

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During a users logon script processing, you can add a registry entry to make the next
login an automatic admin login, with a RunOnce entry to a batch file or other script. Then initiate a shutdown and restart.

When the machine reboots, it should automatically login using the administrative account. Your RunOnce script should remove the AutoAdmin login, and then initiate a quiet install of SW, before doing another shutdown.

If you create a unique Admin account for doing this, you can assign it a
logon script that does the installation instead of using the RunOnce key.
This means that as the user never leaves the logon script they don't gain admin access to the machine during the installation. If they cancel the script it automatically logs them out, and keeps your security.

To do an automatic logon make the following entries.

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"DefaultUserName"="YourAdminAccount"
"DefaultPassword"="AdminPassword"
"DefaultDomain"="YourDomain"
"AutoAdminLogon"="1"

To remove an automatic logon make the following entries.

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"DefaultUserName"=""
"DefaultPassword"=""
"AutoAdminLogon"="0"

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Reduce risk by adding this. It will cause the Login script to run before anything else can be done.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\Winlogin\RunLoginScriptSync

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