I accidently modified a labview library *.vi file. How do I repair my system?

[noobie_programmer]

Dear Sir:

     I work with Labview version 8.5. which operates on Windows Vista O/S.

     I accidentally modified a Labview library *.vi file and now some programs which once ran correctly, no longer run correctly.

The library I modified is named lvsound.llb and the file that I modified was named, "SO Write.vi".

I actually made two modifications, however, the first modification was deleted. 

This is what happened.   I modified the SO Write.vi file by accident, somehow, a connection was severed. 

I thought I could repair the file by copying an identical SO Write file that I had stored on another computer.     What I did was I copied the working SO Write.vi block diagram contents (which was stored on an external drive and not stored in the Labview installation "sound" folder) and then I opened the SO Write.vi in the lvsound.llb (this is the Labview installed *.llb)  and deleted everything in the block diagram and then I replaced the block diagram with the copied block diagram.   I thought this would solve my problems because the copied program did not have a severed connection - no broken arrow icon).     However, I soon found out that programs which ran correctly before the accident, still no longer run correctly after the block diagram content swap.

I have attached a picture of the error message.   

Can someone please tell me the safest way to repair my system?

[noobie_programmer]

For your convenience I upload a reference picture of the labview library that I was referring to.

Please note that one can only view the library contents while the Labview IDE is open.  In other words, to see the library contents one has to be working within the Labview IDE.

[ijustlovemath · Accepted solution]

Don't swap block diagram contents, or if you do, set up the connector pane the same way it was. When you deleted all the controls and indicators, the connector pane was cleared which is why things that call this subVI will not see that it has any controls. To fix it, you need to match this connector pane:

To set it up, click an empty box in the connector pane, then click the corresponding control or indicator. For example, in the bottom left of your new connector pane, click the bottom left box, then click the "error in (no error)" control to let outside VIs pass in an error via the connector pane. To see where everything is connected, I'd recommend you go to a computer with a working version and one by one, click the connector pane terminal and the corresponding control will highlight:

eg clicking the top left corner will highlight the "task ID in" control.

Another option you have is to simply copy the .vi itself (file, not just block diagram) from the working library, delete or rename the current "SO Write.vi", and just drag the .vi file from Explorer onto the LLB manager.

[tst · Accepted solution]

Just take the entire llb file from the other computer and use it to replace the llb file, then open the code. Just make sure that the llb file comes from the same LV version (ideally the exact same details which you can see if you open the about dialog).

The other alternative is to run a repair install, which I believe replaces all the VIs in vi.lib, but that takes longer. You could try extracting the llb file from the DVD, but it's probably in CAB files.

[noobie_programmer]

Dear Tst and Ijustlovemath;

    Thank you both for the great technical support.  

     I learned a lot of stuff from Ijustlovemath's reply.   Thanks a lot - it was a good read.

     I actually tried TST's solution, which was copy and paste a working and identical *.llb file into the Labview sound folded,  because it was the easiest solution.    The copy and replace *.llb method worked.   Thank you TST.

     You guys are great!!!