Help command is not working in command prompt

[khushbu]

help command of command prompt is not working in windows 7 64 bi
and attrib command is also not working
i use mcafee antvirus so its better to use mcafee or not

 

[nhasian]

Here are detailed step by step instructions with pictures:

How Do I Use the Windows System Restore Utility?
How Do I Perform a Startup Repair or Repair Installation of Windows?
How Do I Perform a Clean Installation of Windows?

Also there is SFC How to use the System File Checker tool to troubleshoot missing or corrupted system files on Windows Vista or on Windows 7