No access to HDD any more i.e. it is not seen by the OS

Mac Computers are one of the most popular and advanced operating systems that are used worldwide today. These systems are high performance devices that can fulfill all the user\'s requirements. You can perform all different activities on these high-end computer and MacBook. Still people have faced problems with the Mac based computer systems. The problem was related to hard drive access. When people start their computer, they see message “No Access” in HD permissions. After this your computer boots anything after Mac OSX progress line at startup. People try to start their system in safe mode but the problem still exists.

This is a problem that occurs when people accidentally set the no access permissions on their Mac Hard drives. The solution for the problem “ No access to HDD any more i.e. it is not seen by the OS ” is that if the disk in the question is your Mac OS X startup disk and your computer stops starting up at the blue screen then restart the system with the command and S keys held down and then after enter these commands:

mount –uw /
chown root /
chmod 1775 /
exit

If the disk in question uses Mac OS X but isn\'t current startup disk then opens the terminal in the /Applications/utilities/folder and enters the following:

Sudo chown root "/Volumes/volumename/"
sudo chmod 1775 "/Volumes/volumename/"
sudo -k

You will be asked for your password when executing first command. It doesn\'t appear in the terminal window. Replace the volumename with the actual disk name.

If the disk in question does not have the Mac OS X installed then open the terminal in /applications/utilities/folder and enter the following:

Chmod 775 “/volumes/volumename/”

Replace the volumename to original disk name and then log out and back in. These are some methods when you can use if you see message like “ No access to HDD any more i.e. it is not seen by the OS ”.