VI cannot find shared variable in engine despite successful deployment

[jbailey]

I am unable to use Shared Variables to communicate between VIs located on my PC and the VIs located on my cRIO-9014.  This is a new development as I have been running the same VIs for over a year without this problem.  The only recent development is that the IT department at my company installed new virus protection software and changed some windows firewall settings on the PC that I am using.  This problem first began as soon as I got the PC back from IT.  I have since unblocked LabView in Windows Firewall but that has not fixed the problem.  The error I get every time I try to read a shared variable on the real time target is:

Error -1950679035 occurred at Shared Variable Read in RT Interface.vi

Possible reason(s):

LabVIEW:  (Hex 0x8BBB0005) Unable to locate variable in the Shared Variable Engine.  Deployment of this variable may have failed.

I have redeployed all of my shared variables and according to LabView the deployment was successful, yet I still get this error every time.  Is it likely that something the IT department did with the Antivirus/Firewall software has blocked communication between the cRIO-9014 and my PC?  I have used Measurement & Automation Explorer to check communication with the device and as far as I can tell everything seems fine.

[elset191]

In my experience you have to grant access to your specific IP in the firewall, not just LabVIEW

Message Edited by elset191 on 08-27-2009 02:56 PM

[Anna_K.]

It is very likely these new security measure are the problem. Try again after disabling the firewall and the anti virus software.

[jbailey]

The firewall was disabled but I am still having some issues.  I have been testing the communication with two simple VI's: one on the PC with a switch that controls an indicator on a RT VI via shared variables.  The indicator is lighting up but after a 3-8 second delay and it still gives me the same error message.

[Anna_K.]

Hello,

So the shared variable gets written to and read from properly but after a delay. When does this error occur then?

You should have a small wait ( like 100 ms) in your RT VI to allow the processor to talk to the Shared Variable engine. Are you able to test the RT target with another PC? One that does not have the Virus scanner?

Thanks,

Anna K.

[Anna_K.]

Some helpful KBs

http://digital.ni.com/public.nsf/allkb/A12707C3AA00F5598625737C0066D4F6?OpenDocument

http://digital.ni.com/public.nsf/allkb/F28F3B9E82BF7498862571E2007D615F?OpenDocument

[jbailey]

After adding LabVIEW to the exceptions list of Windows Firewall, my issue seemed to be cleared up.  I am now getting the same error message once again, but now I get it every time I run a VI with shared variables and it actually pops up an error message asking me to continue or stop.  Again, according to LabVIEW the shared variables deployed successfully.  I looked at the two KB articles that were posted and it seemed like this error has three causes:

1-Unsuccessful deployment - everything seems to have deployed

2-Firewall Issues - were taken care of to fix my original problem

3-Shared Variable Engine not running

I've looked around and I found a reference to 'repairing' the shared variable engine but not a guide for how to do that.  I have opened variable manager (I am using LabVIEW 8.5) and have stopped and started the shared variable engine with no effect.

What are steps I can take to ensure the Shared Variable engine is running properly?

[Anna_K.]

Oddly enough, I have been having the same issue. I am currently repairing my LabVIEW due to another issue and will let you know if this fixes the problem. We can also repair the Shared Variable Engine as well. Go to Control Panel >> Add/Remove Programs. Under National Instruments Software choose the software and click Repair in the dialog box.

Thanks,

Anna K.