Scripting

You'll probably find that, during the UI install, you're prompted to enter the name/instance of a SQL Server.

You need to find the name of the property "behind" the text-box and then pass that name and a value for it on the command line. So, let's say the property name is "SQLSRV" and your target server's name is "APP_DB", you need to use this on the command line:

msiexec /i [path_to_and_name_of_MSI] SQLSRV=APP_DB /qb /l*v %SystemRoot%\TEMP\Install_SQLDiags.LOG

Note that I have added logging to your command line.

Also, make sure that any relevant Custom Actions which are in the UI sequence also appear or are set to run in the ExecuteImmediate sequence. It's common for vendors to assume that all installations will be done via the UI and forget to account for silent installs.

Next, you need to be careful about which account you use for installation. The local System account won't have any network access so connections to servers will fail, as will any account which doesn't have access to the target database.

Lastly, your original command line is a mix of vendor EXE command line arguments and those for MSIExec. Extract the MSI and use that BUT...when you've test-deployed your package for the first time, use a lightweight snapshot tool to do a comparison against what the MSI does and what the EXE does (remembering to rename the registry's 'Uninstall' branch first, to prevent Windows Installer believing the package is already installed): it's not unknown for lazy vendors to add code to their set-up stub which really belongs in the MSI.

Your .exe command line is a little off, you're running 'msiexec' with the .exe - you should be running the .exe with a '/S /v...' to pass the parameters to msiexec.
But I don't think that this is your issue, as it only installs when run interactively anyway.

Do you provide any futher information (SQL server name etc.) in the GUI install?
If you don't then there could be a CA that is only running in the 'InstallUISequence' that is generating some configuration needed to complete the install.
You may be able to move the CA into the 'InsallExecuteSequence' to allow it to run in a non-IUI install.

You could also run a verbose log on a GUI install and check the properties populated as it runs through. Compare that to a non-UI install log and see if there is anything you can incorporate into an MST to pre-populate the properties.

Hope that helps,
Dunnpy

EDIT: VBSCab beat to me it - with pretty much the same info!

I think you should create a response file, and try to install silently but with the response file, this will assure all the actions you performed with the UI will be done unnattendedly. If this solution doesn't work, take a look on the msi on the sequence tables, to check if there are some actions on InstallUISequence that are not present on InstallExecuteSequence, and copy them using a transform.

Finally, before doing the avobe actions, assure that you have connectivity to the server  and is reachable.

Hope it helps

 Go to registry:

>The GUI install does not prompt for a SQL instance
Does the EXE install prompt? Stupid question, it *has* to, or how would it know which server/instance to connect to?!? :-)

As stated above, examine the log and find out which property contains that value.

Here is the correct MSI packaging instructions to install the Console only (and PowerShell snapins):