No message appears to enable the statusbar and no welcome screen is shown after re-installation

[passbrains]

Adapted from ​https://www.passbrains.com/dashboard/view-ticket.php?ticket_no=AIN-71

Environment

Windows + 8 64bit + Internet Explorer 11 + Dutch
ABP version 1.2.705.0

How to reproduce

On a system you have never installed addblock before

1. In IE disable the status bar (Disable_status_bar.png)
2. download the installation program from        ​https://adblockplus.org/devbuilds/adblockplusie/00latest.exe
3. Close IE
4. Run the downloaded installation program
5. Start IE
6. A message appears to enable the status bar and a welcome screen is shown (Disable_status_bar.png and Welcome.png)
7. Uninstall Adblock using Control Panel
8. In IE disable the status bar
9. Close IE
10. Run the downloaded installation program
11. Start IE
12. No message appears to enable the statusbar and no welcome screen is shown

Observed behaviour

No message appears to enable the statusbar and no welcome screen is shown

Expected behaviour

A message to enable the status bar and a welcome screen should be shown as is done for after a fresh installation.
(see attachements)

[oleksandr]

This means that we should delete all files when doing the uninstall. That way the "first run" logic would get triggered on re-install.