I installed the beta version you linked to (1.5.99-1805-wk1), and switched on the error logging.
Just now, I lost a window of SQLYog (a MySQL client), so I'm pasting the relevant part of the log file below. I hope it helps a bit in narrowing down the problem.

Let me know if I can be of further help,
wwwald

Log file output:
[code]
13:39:39> >>> Desktopwechsel von 2 nach 1 >>>
13:39:39> Aktives Fenster: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:39> --- Taskbarbuttons auf Desktop 2
13:39:39> Stecke IE in Gummizelle: ExpoViz - Google Chrome (722728)
13:39:39> Stecke IE in Gummizelle: C:\Users\standaea\AppData\Roaming\Dexpot\dexpot.log - Notepad++ (1312824)
13:39:39> Stecke IE in Gummizelle: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:39> --- Stelle 0 Taskbarbuttons wieder her...
13:39:39> ---
13:39:39> Zaubere IE aus der Tasche: Aurora Start Page - Aurora (5178796)
13:39:39> Zeige aktives Fenster Aurora Start Page - Aurora (5178796)
13:39:39> Desktopwechsel abgeschlossen.
13:39:39> Wechselkontrolle: 393468 nicht sichtbar.
13:39:39> Wechselkontrolle: 5048770 nicht sichtbar.
13:39:41> Verschiebe Fenster 3081338 indirekt von Desktop 2 auf Desktop 1
13:39:41> Entferne Fenster 3081338 von Desktop 2.
13:39:41> Kopiere Fenster 3081338 auf Desktop 1.
13:39:41> Zaubere IE aus der Tasche: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:41> Zaubere IE aus der Tasche: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:41> Untokenize failed.
13:39:50> >>> Desktopwechsel von 1 nach 2 >>>
13:39:50> Aktives Fenster: Aurora Start Page - Aurora (5178796)
13:39:50> --- Taskbarbuttons auf Desktop 1
13:39:50> Stecke IE in Gummizelle: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:50> Stecke IE in Gummizelle: Aurora Start Page - Aurora (5178796)
13:39:50> Stecke IE in Gummizelle: (1247882)
13:39:50> --- Stelle 0 Taskbarbuttons wieder her...
13:39:50> ---
13:39:50> Zaubere IE aus der Tasche: ExpoViz - Google Chrome (722728)
13:39:50> Zaubere IE aus der Tasche: C:\Users\standaea\AppData\Roaming\Dexpot\dexpot.log - Notepad++ (1312824)
13:39:50> Desktopwechsel abgeschlossen.
13:39:50> Wechselkontrolle: 393468 nicht sichtbar.
13:39:50> Wechselkontrolle: 5048770 nicht sichtbar.
13:39:51> >>> Desktopwechsel von 2 nach 1 >>>
13:39:51> Aktives Fenster: (0)
13:39:51> --- Taskbarbuttons auf Desktop 2
13:39:51> Stecke IE in Gummizelle: ExpoViz - Google Chrome (722728)
13:39:51> Stecke IE in Gummizelle: C:\Users\standaea\AppData\Roaming\Dexpot\dexpot.log - Notepad++ (1312824)
13:39:51> --- Stelle 0 Taskbarbuttons wieder her...
13:39:51> ---
13:39:51> Zaubere IE aus der Tasche: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:51> Zaubere IE aus der Tasche: Aurora Start Page - Aurora (5178796)
13:39:51> Zeige aktives Fenster SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:39:51> Desktopwechsel abgeschlossen.
13:39:51> Wechselkontrolle: 393468 nicht sichtbar.
13:39:51> Wechselkontrolle: 5048770 nicht sichtbar.
13:39:51> Wechselkontrolle: 1247882 nicht sichtbar.
13:40:05> Hotkey 4 betätigt.
13:40:05> >>> Desktopwechsel von 1 nach 4 >>>
13:40:05> Aktives Fenster: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:40:05> --- Taskbarbuttons auf Desktop 1
13:40:05> Stecke IE in Gummizelle: Aurora Start Page - Aurora (5178796)
13:40:05> Stecke IE in Gummizelle: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:40:05> --- Stelle 0 Taskbarbuttons wieder her...
13:40:05> ---
13:40:05> Zaubere IE aus der Tasche: xplorer² - [Dexpot @ C:\] # gui @ D:\ (2165332)
13:40:05> Zaubere IE aus der Tasche: Inbox - Microsoft Outlook (134916)
13:40:05> Zeige aktives Fenster Inbox - Microsoft Outlook (134916)
13:40:05> Desktopwechsel abgeschlossen.
13:40:06> Wechselkontrolle: 393468 nicht sichtbar.
13:40:06> Wechselkontrolle: 5048770 nicht sichtbar.
13:40:08> Hotkey 1 betätigt.
13:40:08> >>> Desktopwechsel von 4 nach 1 >>>
13:40:08> Aktives Fenster: Inbox - Microsoft Outlook (134916)
13:40:08> --- Taskbarbuttons auf Desktop 4
13:40:08> Stecke IE in Gummizelle: xplorer² - [Dexpot @ C:\] # gui @ D:\ (2165332)
13:40:08> Stecke IE in Gummizelle: Inbox - Microsoft Outlook (134916)
13:40:08> Stecke IE in Gummizelle: (2623152)
13:40:08> --- Stelle 0 Taskbarbuttons wieder her...
13:40:08> ---
13:40:08> Zaubere IE aus der Tasche: Aurora Start Page - Aurora (5178796)
13:40:08> Zaubere IE aus der Tasche: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:40:08> Zeige aktives Fenster SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:40:08> Desktopwechsel abgeschlossen.
13:40:08> Wechselkontrolle: 393468 nicht sichtbar.
13:40:08> Wechselkontrolle: 5048770 nicht sichtbar.
13:40:09> >>> Desktopwechsel von 1 nach 2 >>>
13:40:09> Aktives Fenster: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:40:09> --- Taskbarbuttons auf Desktop 1
13:40:09> Stecke IE in Gummizelle: Aurora Start Page - Aurora (5178796)
13:40:09> Stecke IE in Gummizelle: SQLyog Community - [dbuser @ localhost/my_database - root@localhost] (3081338)
13:40:09> --- Stelle 0 Taskbarbuttons wieder her...
13:40:09> ---
13:40:09> Zaubere IE aus der Tasche: ExpoViz - Google Chrome (722728)
13:40:09> Zaubere IE aus der Tasche: C:\Users\standaea\AppData\Roaming\Dexpot\dexpot.log - Notepad++ (1312824)
13:40:09> Zeige aktives Fenster C:\Users\standaea\AppData\Roaming\Dexpot\dexpot.log - Notepad++ (1312824)
13:40:09> Desktopwechsel abgeschlossen.
13:40:09> Wechselkontrolle: 393468 nicht sichtbar.
13:40:09> Wechselkontrolle: 5048770 nicht sichtbar.
[/code]

[quote="wwwald"]I'm seeing strange behavior too on Windows 7, using the latest Dexpot 1.5.99.1805.[/quote]
For Dexpot 1.6 Beta, see http://dexpot.de/forum/viewtopic.php?p=31153#p31153.

I'm seeing strange behavior too on Windows 7, using the latest Dexpot 1.5.99.1805. I'm using a dual monitor setup, but I don't think the problem is exclusively tied to the second monitor.

The problem: regularly, certain windows (MS Word, Xplorer2, or others) disappear from the desktop. They are still in the Win7 taskbar, but clicking them does not bring up the window, and I can't close them anymore via the taskbar button context menu.
Using Process Explorer, I can manage to make them visible again (right-click process name > Window > Restore), but then I cannot click any of the window's contents anymore. Only way to fix it: kill the process and restart the application.

I'm not able to consistently reproduce yet, but I will post again if I get there. Hopefully you guys can make something out of this already,

Greets,
wwwald

I am having the same issue. I have a rule set to "Move to Desktop X" and check box to "Follow after move" - Usually this happens when I open multiple applications at one time. Also, "Apply rule Automatically" is checked.

I've experienced this with Chrome, Rhapsody and Visual Studio.

The app is still running in the background as a process, but it appears that Windows GUI has lost sight of it, because there seems to be no way to recover the process other than, as a previous user mentioned, ending it and starting over.

OS: Windows 7

OS = WinXP
Dexpot = 1.5.5 build 1302

I am also having this problem, but it does not seem to be related to any desktop in particular. When I switch desktops, occasionally some of my windows disappear from view and also disappear from the taskbar. The applications are still running, I can see them in the task manager, but I cannot find a way to access them, just as described above. I must kill the process and restart it to regain access.

:dex:,

non-reproducible. More info, please.

OS = Windows 7
Dexpot version = 1.5.5 Build 1302

If, with an appliction open on one desktop I double click a file associated with this application on another desktop the file seems to open, but the appliction disapears form the task bar on both desktops. The only way I can currently get around this is to open the Windows task manager and kill the process (the application doesn't show up in the task manager "applications" list on any desktop). I can the restart the appliction, but obviously lose any unsaved work.

So far I've seen this behaviour with:

Foxit (pdf reader)
MS Excel 2007
MS Word 2007
MS Visio 2007
MS PowerPoint 2007

Interestingly, this doesn't happen with Firefox (v3.6.8) or MS Outlook 2007

Am I missing a setting somewhere, or have I found a bug?

tia

JonS