I bought a new iMac preloaded without a backup disc and I now want to reconfigure the administrator as I've forgotten the details I entered initially?
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New Macs do not come with DVDs to reinstall Mac OS X. Instead, you have got OS X Recovery > http://support.apple.com/kb/HT4718
If you have forgotten your user account password, you can still reset it through OS X Recovery by following these steps > http://discussions.apple.com/docs/DOC-4101 You may need to do some work with the keychain after resetting your password > http://support.apple.com/kb/HT1631?viewlocale=en_US&locale=en_US
Retrieving data ...