I have an apparently insuperable dilemma. An InstallScript Basic MSI installer will apparently not launch a second installer. It keeps returning the error -1618 "Another installation is already in progress. Complet ethat installation before proceeding with this install." Unfortuately, the other installation hangs with a "cleaning up back up files" message and a cancel button. The only way to "complete" the first installation is the CANCEL THE SECOND ONE (the one you want launched).
Once you cancel the second installation, you've defeated the whole purpose, which was to install the second application (in this case a common database for multiple applicatins).
At first I thought that using a deferred or commit custom action might solve the problem. I normally don't use those because they are a nightmare. But I got through the process of passing the lauch path to the deferred custom action (bizarre process) and STILL got the -1618 message.
NOTHING -- and I must have tried about eight different methods -- would allow the second installer to run. MSI (or maybe it is InstallScript) required that the second installer be CANCELLED for the first one to finish. There was no way to comply with the error messge and finish off the first installation first.
Nothing works. This is the kind of stuff that makes doing MSI a complete nightmare.
