Thanks a lot. Atlast I get the solution. I have been stuck up since long. So many people helped me. Let me thank to all again.
Now, what was the issue with respect to my last posting ? I did not use the double quote (" ") both in field_name.txt file and output file.
–fieldFile=“C:\Users\Arindam PC\Documents\field_name.txt”
–out=“C:\opt\backups\info.csv”
I also attach the screen shot of complete command-line option of mongoexport.
Regarding my last query : Why did you advise me to put the command on notepad and remove the spaces before each parameter and run command again ?
I understand that he was trying to help me to figure out what exactly wrong was. Since, I was confident that the issue was not due to space problem I replied that way. I also attached the screen shot and pointed out to verify whether the same space issue also exists in the screen shot also.
Anyway , I am sorry for my reply if it sounds harsh.