Hello Boy! 
I am italian, sorry for my english...  
I have a big problem and I do not know how to fix it. 
Using LabVIEW 8.5 
My program is for the management of machines voltage regulators, i communicate with them via a USB-RS485 on Modbus, The questions I wished them and so far no problem. 
stores data in a spreadsheet excel and do extensive use of blocks "read from measurement file" and "write to measurement file" about 30 times that i frequently rewrite about once every 2 seconds. 
Now I go to my problem: after that the software go regularly he stops suddenly. 
No longer works in labview converter but I do not return any error message or something. 
At this point I press the stop button and i restart the program and everything starts, until a new stop. 
My fault, software, or the converter?? 
thank all