Related Videos: Lower Back Strain Video. Lower back strain is caused by damage to the muscles and ligaments of the back. Learn about muscle anatomy and the symptoms of lower back strain. Back Strains and Sprains Video. A muscle strain or a muscle sprain in the back is the most common cause of back pain. A muscle strain happens when the muscle is over-stretched or torn, resulting in damage to the muscle fibers (also called a pulled muscle). 2  A lumbar sprain happens when ligaments are stretched too far or torn. 3  Ligaments are very tough, fibrous connecting tissues that connect bones together.
The invalid SIM card error is typical of the type of error you get if your phone is locked to a different carrier than what you have. Many people offer unlocking service and typically charge between US $5 and $15 plus shipping to unlock your phone.he invalid SIM card error is typical of the type of error you get if your phone is locked to a different carrier than what you have. Many people offer unlocking service and typically charge between US $5 and $15 plus shipping to unlock your phone.
Don't attempt to guess your PUK code. Multiple incorrect entries of the PUK code -- generally 10 -- will cause your SIM card to be permanently disabled. You'll then need to purchase a replacement SIM card. If your SIM card is blocked, you can still make emergency phone calls.If you want to avoid having to enter your PUK code in the future, you can disable the SIM card security lock in your phone's security settings. This will turn off the request for the PIN code when your phone is powered on.f your SIM card is blocked, you can still make emergency phone calls. If you want to avoid having to enter your PUK code in the future, you can disable the SIM card security lock in your phone's security settings. This will turn off the request for the PIN code when your phone is powered on.