Hello,
there are a lot of options suggested around the internet, but did you try the below ones to resolve this issue:
-Disable "Restart Manager" by making use of MSIRESTARTMANAGERCONTROL= "Disable" in the property table. This would kick in the legacy "FilesInUse" dialog box. In your case, The FilesinUse dialog might also not be displayed (since services do not have a window associated with them) The "FilesinUse" dialog box does not list processes which do not have a window associated with them. So, in your case, disabling the Restart Manager, might not display any dialogs(neither FilesInUse nor RestartManager).
A reboot might be required, not necessarily because of your services but due to some other process which might be holding your files in use. If you think that there could be no other process other than your own services holding files, then go ahead and follow this approach . If you think that there could be other processes, other than your services holding files, then having "Restart Manager" enabled is ideal. Not having "Restart Manager" will either result in one of the things:
-Display the Legacy FilesInUse dialog asking you to shut down the processes listed in the dialog. This might result in you having to shut down these processes via a custom action.
Both the "RestartManager" and "FilesInUse" dialogs are displayed by the "InstallValidate" standard action. If you want to suppress both of these dialogs, then ensure that your custom action is scheduled before "InstallValidate" standard action. There is a catch here. Scheduling such a custom action before InstallValidate would have to be an immediate mode custom action(You cannot have deferred mode custom actions before "IntsallFinalize"). So , in cases where you are not running as an administrator(such as in UAC enabled scenarios), you might not have the necessary privileges to shut down applications. So , a restart might be required.
-You can also shut down applications using the using the WiX util extensions CloseApplication() function.
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