Wix - ServiceControl start takes four minutes to fail, should be 30 sec

Question

My service automatically starts during install...

Answer 1

The installer has a custom UI which asks the user to copy-paste their connection string given to them from support department. The installer edits a JSON file in the app folder using a deferred CustomAction. It is deferred because it needed to be after the files are written to the disk and it also needed to have elevated permissions. This all worked great until I decided to have the service start itself "at the end" of the installation. My first attempt was to use a

But that was taking 4 minutes to fail. Troubleshooting showed that the service was being started BEFORE the custom action which writes the connection string into the JSON file. I needed the service start to be delayed till after the custom action. I looked at adding a second ServiceControl entry into its own component that could be scheduled much later but that gave me an uncomfortable feeling that I was going to break uninstall and repair installs. So, I just added another deferred custom action sequenced right after the JSON file edit. That new action executes "SC.EXE start MyServiceName". SC.EXE is a non-blocking way to start services so succeed or fail, it will finish quickly.

My final solution:

You should note that the ServiceControl entry above does not have a "start=" The DLL that GetConnectionString and SetConnectionString calls is one of my own making. Wix has its own custom action for running command lines quietly... WixQuietExec

Starting the service is just a convenience so for the installer to prevent going to Services.msc to perform the start or requiring a reboot. So I used Return="ignore". Also SC.EXE just puts the service into "Start Pending" so it probably can't return much of an error unless your service doesn't exist.

NOTE: WixQuietExec is documented here. Make sure to quote the EXE and give your property the same Id as your CustomAction that uses WixQuietExec. That info is under "Deferred Execution" but I still got it wrong on my first try.