i is in range of the QStringList

Read_Request_Time.at(i) = "123,456,789"

Opening the file for writing:

QFile fp(fileName);
if (!(fp.open(QIODevice::WriteOnly|QIODevice::Text)))
exit(-1);

QTextStream out(&fp);

then I am doing:

if (system_name.at(i).size() > 0)
out << "System_Name" << "\t" << system_name.at(i) << "\n";

with numerous QStringLists SUCCESSFULLY!! ???

until I get to:

if (Read_Request_Time.at(i).size() > 0)
out << "Read_Request" << "\t" << Read_Request_Time.at(i) << "\n";

this write cause an application error and crashes. and Read_Request_Time.at(i) does contain valid data. "123,456,789"

Curious!!