I found your other thread... The W580_R8BA024_MAIN_GENERIC_LA_RED52 is good.
If you tried with two distinct firmwares, then it is a hardware problem... Maybe there is a contact error between battery and phone.

About SIM lock problem: if in >*<<*<* menu all padlocks are open then your phone is unlocked. What you mean about "it will only accept the sim card"? What is the exact error message?