Vista's "Show Compatibility Files" and the Scrumptious Wonder that is File Virtualization
I was trying to convert some (totally legal) video files into MP4 format for use on my iPod for an upcoming trip to Arusha. I used the Videora iPod Convertor, by the way. By default Videora is set to write to: C:\Program Files\VideoraiPodConverter\Videos so I opened an explorer window and watched that folder for my output files to show up. After hours of converting. Nothing. I searched my hard drive high and low. Nada. What was it chewing on so long? I should have at LEAST 2 gigs of MP4s now. Where are they. I tried again. Hours past. Nothing.
What's this button "Compatibility Files?"
Um, OK. Click.
Then I remembered. In Vista the rules are that if you don't have explicit (by requesting) elevated permissions to write to C:\Program Files, the system lets you think you are writing there but actually redirects (virtualizes) your writes elsewhere. Jerry has some details here, where I took the next picture from.
On the surface, this sucks in a huge way, especially for my Mom in the "where are my files" kind of way.
As far as programs on my system, there's a number of "mal-behaved" programs that are getting their writer redirected to the "Virtual Store." Of note are MSN Messenger, the new Nero, and FireFox.
Ideally apps will write to the places they should be writing to, like Isolated Storage and such. Apps like Videora should include a manifest that explains what they're going to need (security and permissions demands) so that the consent dialog (run my Consent.exe of all things) would be issued automatically.
Personally, I'd rather see a UI with a link or button in the folder rather than in the Toolbar. It is pretty important and blends in there.
The other really bad UI issue is that there's no way to get to the compatibility-based Virtual Store from the common file open/save dialogs.
The same redirection CAN happen with apps that try to write to registry in HKLM, so watch for that also if something "goes missing."
I can see how hard they're working to make Vista more secure while still maintaining extensive backward compatibility. I haven't had any apps (other than one Java app) bork under Vista yet, but things like this Virtual Store will be confusing until new minor releases of apps with a modicum of Vista-awareness come out.