Fix Version/s: None
They do reinstall instead of uninstall.
( https://web.archive.org/web/20160326094601/http://www.7-zip.org/a/7z920.msi )
Steps to reproduce:
1. Download 7zip (link above).
2. Install 7zip.
3. Check if it is works.
4. Uninstall 7zip.
5. Observe that it is still installed.
Debug log attached, but I found nothing insteresting there.