Picasa, a network drive and the lost folders

Summary

1. Be very careful when using Picasa with folders on drive letters that may have unavailable contents, or drive letters that may change

2. Be very careful when using Picasa with folders on a network drive

Details

So here's the scenario:

I have an external LaCie 120GB drive, G:
Since my internal drive didn't have enough storage, my Picasa is set up with folders both from C: drive and (older) folders from G: drive

Now you see it...

But the LaCie is dying, as all hard drives will eventually.
I copied all of the LaCie over to a new, larger C: drive, and to my network storage, a DNS-323, M: drive

Redirecting to these new directories should have been as easy as putting a .bat file in C:\Documents and Settings\All Users\Start Menu\Programs\Startup\

@ECHO OFF
SUBST G: M:\Virtual_G
CLS
EXIT

Then shutdown, remove the external drive, and start up again.
Except it turns out that Picasa does not see the new G: drive.  Or maybe half-sees it.
It is fully accessible through Windows Explorer, although the new SUBST drive does say "Disconnected Network Drive" for some reason.

Now you don't...

I don't know if this is a behaviour unique to the DNS-323, or whether it's generic to all Windows network drives.

This would be no problem, one would think.  Switch back to the old drive, right?
Except it appears, that in some cases, when Picasa sees a drive but doesn't see the files/folders it expects, it removes those folders and files from its database (the "Picasa Library").  It forgets about them completely.
So when I reconnected my external drive and fired up Picasa again... all the thousands of files from dozens of directories were no longer there.

(SIDEBAR: Just to be clear, the files and folders are not deleted from the physical storage, they just no longer show up in the Picasa display (Library Folders).  Nothing has been lost except a day's worth of time organising folders inside of Picasa.  Also, in case you're wondering why I can't just do a complete rescan, there are many many duplicates and different versions of files and folders on the G: drive, since it holds multiple backup copies.  END SIDEBAR)

This is a fundamental flaw in Picasa.  At a minimum it should pop up a warning along the lines of "unable to locate folders on G: drive, remove from Picasa? (Yes/No)".  But it doesn't, it just silently eliminates them from its database.

Just to make things even more confusing, this behaviour didn't seem to be consistently repeatable.

That is, sometimes when I set up folders from the external drive, test with the network drive, and then switch back, they show up again, sometimes not.

Switching does work for SUBST to folders on the internal drive, e.g. if I set up folders from the external drive, and then point to the copies on the C: drive

@ECHO OFF
SUBST G: C:\L120\G
CLS
EXIT

There's no problem.

UPDATE: It looks like this might be part of the problem

On a computer has Windows Internet Explorer 7 installed, you create a disconnected network drive by running the subst command at a command prompt. When you open this network drive in Windows Explorer, it appears as Disconnected Network Drive. Additionally, the security zone for the network drive appears as Internet in the status bar.
However, on a computer that has Internet Explorer 6 installed, the security zone of the network drive appears as Local Intranet in the status bar.

http://support.microsoft.com/kb/941000

There is a hotfix available, but you have to go through Microsoft Support to get it.

UPDATE: The way I work with my photos is maybe a bit unusual, I don't want any duplication inside of Picasa (other than Picasa Exports).  There's some discussion about the Picasa folders issue in a Picasa Help  thread: Picasa forgets folders it can't find

Comments

[Tim]

It's not the subst command at fault. Definitely Picasa forgetting folders.

I mapped a network drive through the UI on my laptop (same as doing a 'NET USE' command), and sure enough when I go take my laptop elsewhere and use Picasa to view my local photos, it loses all the network photos. Being there are many thousands of them, and over a network, it takes hours to reindex them!

[Jeff H]

Using the folder manager, would it help to turn off "Always Scan" for the network locations and just use "Scan Once".

[Steve M]

Jeff H's suggestion is right on target. One would expect that "Scan Once" would not care if a file, folder, or entire drive is added or removed once the scan is complete. But I have the same problem: If I move the laptop to a different network the drive, instead of becoming unavailable, is completely removed from Picassa.

Hopefully they will see the light soon.

[Steve Logan]

I'm in the same boat with the DNS-323. About 3 days ago some of my folders that are on the DNS-323 vanished from Picasa. Nothing I could do could seem to get them back. So I uninstalled Picasa, selected YES to remove the database, rebooted, downloaded a new version and reinstalled. To my surprise, it still had the mapped drive listed as a folder to scan (so much for a clean reinstall!!). So it seemed to be scanning when I went to bed last night, but when I woke up this morning it had only scanned about 5 folders (out of around 400). This is extremely frustrating. I purchased and setup this network drive to provide security for our roughly 15gb of digital images, and now I hit this roadblock. And it seems that Picasa is really the only game in town for digital photo management.