How do I stop excel from opening when I run the following code?

[crossrulz]

Try something like this.

[nyc_(is_out_of_here)]

You are leaving Excel running in the background.

Close all your ActiveX references.

[xochitlga]

I have try all the suggestions mentioned above however, I am still getting the same messages

[RavensFan]

You have a race as to which Close function happens first.

You should use your error wire to determine the order of execution.  And the order of execution should be to close the references in the reverse order of the way they were opened.

[nyc_(is_out_of_here)]

There is no need for Sequences. Dataflow will work.

You are closing your references out of sequence.

Again, did you even look at the examples that came with LabVIEW????

[xochitlga]

Thanks for the help

But now I am getting the following error:

LabVIEW: A null or previously deleted refnum was passed in as an input

[RavensFan]

You're still not getting it.  Pay attention to the order of your green wires.  You are closing the application reference before you are closing the workbook reference.  Plust you are quitting the application and close references in parallel to working with the cells.

You also have a race condition by using a local of the indicator called "String".  The local is likely to be read before a value is written to it.

[RavensFan]

Try this.

You'll see I tried to sort out the order of objects so you are closing them in the reverse order of the way they were opened.  Also, to make sure that something isn't closed until after it is done being used.

I don't understand what you were trying to do with the file open stuff before feeding the workbook filename to the open function.

[xochitlga]

Thanks for all your help, when I run your VI I do not get any error's and the windows explorer shows the xls file was modified, however, when I open it, the cell color has not changed?

[RavensFan]

It worked for me.  Though the one thing I noticed was that the color in Excel is different than the color in LabVIEW.  I think the color coding scheme is different between the two applications.