Re: About patch 1.38/Error during start up. Please see the log for more details

Did you try the suggestions here: http://answers.ea.com/t5/The-Sims-3/Error-during-startup/m-p/1220#M70 and in my blog: http://sims3.crinrict.com/en/2011/03/error-there-was-an-error-during-startup.html

You most probably have a not-matching registry key somewhere.