Sims start up/Where is the Log

I've been trying to get on to my Sims 3 and overtime I click it on my desktop it says "Error during setup. Please see Log for more details." I have no idea what that means or where my Log is. At first I thought it was because I uploaded 4 sims at a time so I took them off ad tried the Sims I already had. That message kept on showing up. Can you please tell me how to fix this.

Thank you,

Logan.