Uninstaller does not work when started from Control Panel on Vista x64

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Compile example2.nsi sample script distributed with NSIS
2. Install on Vista x64 (tried here on Vista x64 Ultimate SP2), accepting all 
defaults
3. Open Control Panel -> Programs -> Uninstall a program
4. On the "Uninstall or change a program" page, select "NSIS Example2" and 
click "Uninstall"

Expected output would an UAC prompt followed by the NSIS uninstaller being 
started.
Instead, you get an UAC prompt followed by a Vista "Programs and Features" 
error message box with the following message:

<message box text>
"An error occurred while trying to uninstall NSIS Example2. It may have already 
been uninstalled.

Would you like to remove NSIS Example2 from the Programs and Features list?"
</message box text>

However, the uninstall information in the registry seems to be correct, and the 
uninstaller itself works fine when started manually from its path C:\Program 
Files (x86)\Example2\uninstall.exe

This problem seems to be specific to Vista x64. Everything works as expected on 
Windows XP x64 SP2 as well as on Windows 7 x64 SP1, as well as all 32-bit 
XP-and-newer x86 OSes including Vista Ultimate SP2 x86.

What version of the product are you using? On what operating system?
NSIS Unicode 2.46.5
Windows Vista Ultimate x64 SP2 + latest patches from Windows Update

Original issue reported on code.google.com by stefan.l...@gmail.com on 18 May 2012 at 5:30