After installing a new account on the internal harddisc after software problems, my MAC OS 10 went into lock. Not only the internal harddisc, but also my three external harddiscs. My MAc says I don't have the priviliges to unlock, which is not the case of course. If I go to 'info' I can unlock the lock icon on my user account, but from then on the MAC does not respond to any commands or changes I would like to make.
Can anybody help me?