"Can't run 16-bit Windows program. Cannot find file C:\PROGRA~1\QUESTS~1\Tuning_Lab\Unwise.exe" e (4229612)

I tried uninstalling Quest SQL Optimizer 7.4.1 using Quest installer and at the end of the uninstall a pop-up window comes up saying:

Window Title:Cant run 16-bit Windows program
Cannot find file C:\PROGRA~1\QUESTS~1\Tuning_Lab\Unwise.exe (or one of its components). Check to ensure path and filename are correct and that all required libraries are available.

I have verified the path and the file exists. I looked in the Add/Remove Programs and there is still an entry for Quest SQL Tuning for Oracle. Optimizer itself has been uninstalled and its directories empty, but the Tuning_Lab directory is still there with files.

Cannot uninstall with Quest Installer or Add/Remove Programs.

Issue of the SQL Tuning v6 installer because 16-bit components of the InstallShield software used.

WORKAROUND:
Uninstall Optimizer through Quest Installer, thenmanually delete Tuning directory without wizards.

To remove the entry in Add/Remove program list:
1. Click Start | Run and type regedit in the combo box and press ok button.
2. Then directly go to the following key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Quest SQL Tuning in the registry editor.
3. Delete the Key Quest SQL Tuning and also its subkeys.

STATUS:
Waiting for fix in a future version of Quest SQL Optimizer for Oracle.

Disclaimer : Quest does not provide support for problems that arise from improper modification of the registry. The Windows registry contains information critical to your computer and applications. Make sure you back up the registry before modifying it. For more information on the Windows Registry Editor and how to back up and restore it, refer to Microsoft Article ID 256986 "Description of the Microsoft Windows registry": http://support.microsoft.com/default.aspx?kbid=256986