Sorry for bringing up such a old topic, but I am having the exact same problem, even with the same program. When I use Firefox full screen on my second monitor, the taskbar sometimes gets stuck behind the screen. If I window Firefox, click on the taskbar, and maximizes Firefox again, the taskbar is in the front of the window.

Setup:
Windows 7 Professional 64-bit
DisplayFusion Pro v4.0.1
Auto-Hide: Enable
Show taskbar when app lose focus: Checked

I have installed the beta and will let you know if the problem comes back. I will make a post in a few days if it does not.

Nope, just had the problem again.

Ok, I just got it to repeat itself. When I started the log, the taskbar was actually behind my window at the time, but I figurd that it would not be helpful in the log. The first time is at July 9, 17:50, which should be the start of the log. The second time is today, July 18, 17:30.

Edit: I attach a slightly newer log, to also log when I brought the taskbar back into focus, at 17:37.
Edit 2: Apparently you cannot reattach a file with the same name twice.

Well it took a month, but it finally happened again. I am attaching three files this time inside a zip file. The first troubleshooting file is when the taskbar is still behind the window. The second one is after I click the taskbar. The last file is the log. This happen at around 15:45 today.

Hi!
I am jumping in on this thread, since I have found a way to reproduce this bug with any maxmized window:

1- Set the taskbar to autohide
2- Maximize a window on your secondary monitor.
3- press the windows-key on your keyboard to open the start-menu (it doesn't matter if you do this on the primary or secondary 4- monitor)
5- Click on the maximized window to give it focus (or switch to it via alt+tab)

The taskbar is now hidden behind the maximized window!

I hope this helps.
I have tested it on a bunch of different applications (including Outlook, Chrome, Windows file explorer)

I am using Windows 7 Pro 64bit.
I can reproduce the problem with described steps any time - even after a fresh reboot.

I'm getting the same problem with all windows. The taskbar autohides correctly but frequently pops up behind windows.

Windows XP

I have not changed the dpi scaling from the standard 100% that Windows is "born" with.

- - -

By the way the problem doesn't only happen, when I use the windows-button, as described in my step-by-step - this was just a way I found to consistently reproduce the problem.
It happens intermittently while I'm working on my machine - and I'm fairly certain, I haven't used the startmenu at all.

I can also confirm this is happening. Some hopefully relevant info:
- Occurs when on monitor "3" (untested on #2, no taskbar auto-hide on #1, #1 uses 'Windows' taskbar anyway), monitor order left-to-right 3-1-2
- Monitor 3 resolution is 1080p - 10% of pixels on each axis (crappy HDTV workaround, custom resolution in nVidia control panel), main #1 is 1920x1200, #2 is 1920x1080 rotated to portrait orientation
- Taskbar unhide works normally until Win key is pressed, with Firefox maximized, then taskbar doesn't unhide when I mouseover bottom of screen
- When this happens, pressing Win key only shows icon of start menu in bottom left, which moves upward as though it is on the taskbar unhiding itself, but taskbar itself does not appear
- I can see on the bottom (1 pixel-ish) line of the screen that shows the taskbar unhiding (moving upward) behind Firefox, as though Start menu icon it is on a different 'layer' than the taskbar itself, which is unhiding as well
- Minimizing then restoring Firefox causes taskbar unhide to function correctly again, until Win key is pressed again with Firefox maximized...
- No DPI scaling (default 100%), though I often do zoom within Firefox
- I have the option to force all applications to open on 'active' monitor set.

Win 7 x64, nVidia GTX 560 Ti driving monitor 3 on HDMI, monitor 1 on DVI, nVidia 200 series driving #2 on DVI
I know I have a weird screen setup so thought it may be worth noting since you're unable to reproduce the issue.

Hope this helps... honestly this app is awesome otherwise! Other multi-monitor helper apps don't really play nice with my CAD software...

Would be willing to try Beta (or Alpha ) version to help bugtest this... or provide additional information if you think it would shine any light on this.

The latest beta (5.1.0 Beta 3) fixed the issue for me.

I just installed the latest 5.1.0 beta, and the procedure, I listed, can no longer provoke the issue.
I'll report back later today, when I have have some time to evaluate whether it stays on top or pops behind by itself during work.

Right...
appr. 7 hours of testing now.
I still can't produce the error deliberately.

It did however happen once after appr. 2 hours by itself.
However it was easily fixable by simply pressing the windows-key, which made the taskbar pop up on top again.

It has not happened again since, so I am a happy camper right now!

Just thougt I'd do a quick followup.
I have used this computer for 7-8 hours daily, since my last post, and the problem has not occured even once!

Thank you very much, for continuing the work, until a fix was found!