As I said before, you need to identify the type of uninstaller and find a suitable switch which does what _?= does in NSIS uninstallers. And I don't mean to write NSIS script to do the conversion lol... you need to follow the tasks the 3rd party uninstaller does and do those tasks in your NSIS uninstall script. Run the 3rd party uninstaller from a sandbox such as Sandboxie. That is what I have done in the past.
Stu
How to use switch /sms?
33 posts
There is one related issue with using _?= option. Since _?= stops uninstaller from copying itself to the temporary directory, as the result, the uninstaller couldn't be removed(it couldn't remove itself). Since the uninstaller couldn't be removed, the folder where the uninstaller is located couldn't be removed. I wonder if there is way to keep two good things at the same time. One good thing is allow ExecWait to wait for the uninstaller to finish. Another good thing is still allow users to remove the whole folder where the uninstaller is located.
Copy the uninstaller to $PLUGINSDIR and then run it from there with _?=$INSTDIR.
Stu
Stu