SIM cards, like computers, can crash.
If your mobile phone's Subscriber Identity Module card, or SIM card, crashes, there are a few things you can do to rectify the situation, or at least troubleshoot to identify the problem. SIM cards are extremely sensitive devices and are subject an assortment of issues that can cause them to malfunction or cease to operate at all.
Damage
A damaged SIM card can lead to a crashed SIM card. In situations where a SIM card is frequently transferred between phones, the card can become scratched or damaged, causing it to lose the data stored on the device and to eventually crash. SIM cards contain a small microchip containing important information including the mobile device's phone number and serial number -- which identifies the device to its wireless service provider, which then grants the device access to its network. If you suspect the SIM card's crash is due to damage, contact the carrier for a replacement card.
Incompatibility
Most SIM cards are designed to work with phones that are capable of connecting to a particular wireless network. For instance, a 2G network phone is initially equipped with a 2G-compatible SIM card. Mobile phones designed to access the 3G network are equipped with 3G-compatible SIM cards. At the time of publication, the 4G network is beginning to gain widespread use and is compatible with mobile phones designed with 4G network technology, including 4G SIM cards. Typically, the newer SIM cards are backward-compliant with previous networks. If your mobile phone contains an outdated SIM card, the card may crash, at which point you will need to obtain and install a SIM card that is compliant with your device.
Contacts
One of the unique features offered by SIM cards is the ability to store a phone's contact information, such as phone numbers, which can be transferred from one mobile phone to another. Because it has limited memory space, the SIM card may crash if you attempt to add more contacts than it is capable of holding. If you need to transfer the contact information from one device to another but the SIM card has crashed, transfer the contact information using the device's Bluetooth wireless technology. Most phones that contain Bluetooth feature the Phone Book Access Profile, which allows you to transfer contact files from one device to another.
Considerations
Like computer hard drives that crash, contact data lost due to a SIM card crash is usually irretrievable, making the card useless when installed into another mobile phone. Most of the data stored on a SIM card is put there automatically by the phone for identification purposes and is contained in the device's internal memory, as well. When a new SIM card is installed in a phone, the phone's required identification data is placed on the new card. However, any contact data placed on the card is lost, which is why it's wise to save contact files to the phone's memory as well as the SIM card.
Tags: card crash, mobile phone, contact information, transfer contact, your mobile phone, access network