I tried your solutions to restore audio on my Dell Inspiron 6400 by running Microsoft updates and installing audio drivers from Dell but problem persists. Computer states ''IDT High Definition Audio Codec (Code 10 error). Thank you for your help
Computers & Internet - Dell - Inspiron - Inspiron 6400 Notebook
Answers & Comments
The solution at: http://www.fixya.com/ThreadView.aspx?prdid=484539 should have worked, namely the part to access http://support.dell.com and select the "audio" drivers for your version of Windows (XP? Vista? 7?) and download/install them.