open task manager close all unwanted processes.. format the pen..
close every program except these ..kohommada itin danne unwanted programs gana??
close every program except these ..
explorer.exe
svchost.exe
services.exe
winlogon.exe
csrss.exe
smss.exe
System
System Idle Process
lsass.exe


as well i think may be useful of ending explorer tree...
Task manager - Processes - right click on "explorer.exe" and end process Tree...
Then Restart explorer.exe
Applications tab - New Task - type explorer - press Enter
Then try to format it...




