Labview locks Windows task bar

[PaulyCopeyman]

When my VI is running the task bar freezes, the clock no longer updates and you can't click on other applications. This happens even when no processing is going on. You can still change to other applications using alt + tab.
What setting is causing this?

[Khalid]

Hello Paul,

It depends. What version of LabVIEW and what OS are you using?

The first thing I would check is if there are loops in your VI without any delay fucntions in them. This would make the loops run as fast as they can without yielding to other tasks. There can be other causes as well.

Is it possible to strip down the VI to a bare minimum where the problem still occurs and post it up here?

Regards,

Khalid

[PaulyCopeyman]

I am using Labview 7.1 and Windows 2000.
Even when the VI is idle I get this locking effect.
I have attached a stripped down VI which demonstrates this.
Thanks.

[Dr._Imad]

I was not able to reproduce it on my win 2000/ LabView 7.1
Is this happening with this particular vi, or any other vi ?

[Khalid]

Hello Paul,

I tried this on my LV7.1 and WinXP and it doesn't seem to lock-up the task bar. It seems to respond just fine to all the button clicks.

Do you see this locking behavior even when you only open the VI (not run the VI)? That would be a little weird.

Like Dr. Imad asked, does this happen with any other VI? Did you check what process/application/service is taking up the CPU power?

Sorry for not being of much help here..

Khalid

[PaulyCopeyman]

This effect is only seen when the VI is running.
This is the only VI where I have had this effect.
I have checked task manager and the CPU is running at 0%.
I have just discovered, by accident, this only happens when the window is maximised.

[Dr._Imad]

Hello Paul

I maximized the vi, and yet it did not duplicate what you are seeing.
However, NI engineers are aware of a different bug (that I reported) in version 7.0/7.1 that has to do with a window being maximzed

[christian.karcher]

I know, this thread is a liiiiiittle bit old, but since I had the pleasure to work with LabVIEW 7 again and stumbled upon the same misbehaviour, I thought it might be good idea to present my solution to this problem (as it is the only thread concerning this problem):

I managed not to basically "crash" the taskbar by maximizing the front panel during the execution by opening a reference to the vi and modifying the property node "front panel window" -> "state" to "maximized".

It does not answer the question why exactly this taskbar lock is caused, but at least it's a workaround.

[rolfk]

I have seen similar weird behaviour caused by the video driver in the past. And recently on my Windows 7 system, but not limited to LabVIEW only, although it is the most used application here. The recent failure basically made itself apparent in that mouse clicks didn't seem to register anymore in different windows. It usually started in VirtualBox after the computer had been left unattended for some time, then affected Firefox and also LabVIEW. Sometimes Ctrl-Alt-Del and going back to Windows afterwards cleared it up momentarily but it always returned.

Various google searchs and trials further, I came across a report that this could be caused by NVidia drivers so I updated my video driver and haven't seen such an issue since.