Permission Denied Error when calling Matlab script from LabWindows​/CVI

Question

Hello,
I am reading in data from a DAQ and am writing it to a .csv file in LabWindows/CVI.  I am then sending this data to Matlab to be filtered.  I would like the filtered data to be accessed by LabWindows/CVI so that I can display it as a strip chart.  I have gotten everything to work except the writing to a file in a Matlab script that is called from LabWindows/CVI.  I am basically using the shipped example in found in the activex demo. (http://zone.ni.com/devzone/cda/epd/p/id/2994). I select the script that I want to run and each time it tries to open a file with write permissions I get a "Permission Denied" error.  This occurs when using fopen() in Matlab.  I have also tried using csvwrite() as well as dlmwrite().  Each one gives me a similar error.  The script currently does not try to do any data processing.  It just opens the file, if it is successful it then prints "hello" and then closes it.  The script works well when it is run in Matlab, just not when it is called in LabWindows/CVI.  Below is the script.  Any thoughts, comments or suggestions are greatly appreciated.  I am also open to using other approaches for sending data between Matlab and LabWindows/CVI.  Thanks in advance!!
fclose('all');
[file, errmsg] = fopen('out.txt', 'w');
if(file<0)
    disp(errmsg)
else
    fprintf(file, 'hello');
    fclose('all');
end;
[file, errmsg] = fopen('out.txt', 'w');
if(file<0)    
disp(errmsg)
else  
 fprintf(file, 'hello');    
fclose('all');
end;

Answer 1

I am using Windows 7.  I am running CVI as an administrator and was able to get rid of the "Permission Denied" error by going into the User Account Controls in windows and changing it to "Never Notify".  However, this did not fix the problem of Matlab not being able to write to a file when the script is run from CVI.  In the Matlab code below, It now gets in to the "else", suggesting that fopen() returns a good file handle.  After getting in to the else statement, it will not actually write to the file, nor does it create it.  However, I can make changes to the plot settings and those appear.  Everything is functional when run from Matlab but when run from CVI, things get screwy with opening the file for writing.  It handles the read well.  It seems like there would have to be some file permission errors but, in the CVI program, I open and write to the file "in.csv".  Any help is greatly appreciated.
clear;
fclose('all');
t = zeros(1000);
t = csvread('in.csv');
for i=1:1000
    t(i) = t(i)*4;
end;
[file, errmsg] = fopen('out.txt', 'w');
if(file<0)
    disp(errmsg)
else
    fprintf(file, 'goodbye');
    for i=1:1000
        %t(i) = t(i)*3;
        fprintf(file, '%f,', t(i));
    end;
    fclose(file);
    plot(t/3, t);
    ylabel('t');
    xlabel('Time (s)');
    title('Is this really working?!?');
end;
Thanks,
Chris