Gayatri,
we do not control your PC environment. So if the same boards works with some PCs but not with others (or has intermitent failures) I assume this is due to your PC setup. Please ask your IT experts for help. You may try to remove the USB driver and re-install. See here: c:\TI\ccsv5\ccs_base\emulation\windows\xds100_drivers\ftdi\
Regards,