Introduction Now-a-days mobiles are the signal of our presence! If we switched off our cell phone then we will be de-touched from the world! Now if such a important thing is affected by a virus or stopped working then? My purpose of writing this article is to let you know about some back features of mobile phones, using which we can solve some problems or we can study our mobile phone, even we can measure the temperature too! (I'm Not Joking!! ) Now, if some one asks you, which brand of mobile do you sue? Maximum of us will ask about NOKIA (Except Me!)! In this article, we are to discuss about Nokia, Samsung and Sony Ericsson mobile phones. Okay, Lets differentiate mobiles into categories: 1) GSM 2) CDMA 3) WCDMA or formerly known as 3G mobiles. Now, what is GSM? - Global System for Mobile CDMA? - Code Division Multiple Access. WCDMA? - Wide Band CDMA. Basically in India, we use GSM and CDMA. Another thing is important in mobiles, which is IMEI number or International Mobile Equipment Identity Number for GSM mobiles and RSN number for CDMA handsets. This numbers are unique for each mobiles. If you have a mobile with invlid IMEI then you can face this problem "NO NETWORK COVERAGE" appers on the screen! To check your mobile's IMEI whether its correct or not, CLICK HERE. It also tells you the model number and manufacturer information of your mobile. To know the IMEI of your mobile, please press *#06#Nokia Mobiles In Nokia mobile phones, we basically face some common problems and I'm going to give a common solution to that problems! 1) After pressing GO TO button, your phone restarts? 2) In Nokia 3110c, the music player is always updating the library? 3) No ring tone sound, though you hear the caller's voice? 4) Your NOKIA 6600, 3260 or N70, N72, N73 whatever, sounds SMSes till your balance goes to ZERO? 5) Your N-Series mobile running too slow! All these problems can be solved only by using two codes. *#7780# and *#7370# Now, what is the purpose of these codes? These are Master Reset codes. Caution: Using these codes will erase all user data e.g, phone book, sms etc. So, use it when needed, but before proceeding create a backup of your phone by using Nokia PC Suite. Study Your Nokia Mobile Phone *#0000# S/W version. *#92702689# This will explore all information about your mobile, even the security code (only for CDMA mobiles)! Some more secret codes: *#67705646# Clear operator logo. *#7328748263373738# Resets security code but not works on all models. *#746025625# Battery saving s mode actually this code will turn off the SIM clock. Formatting Some Nokia Mobile Phones Here is a simple process, by using it you can format your Nokia mobile phone having a Symbian OS. Remove SIM, MMC and battery. Then insert the battery again and then press *, 3 and Left Soft Key at a time and then power on the mobile. Continue holding these three buttons till the word Formatting... appears! Samsung Mobiles Some common problems (again)!! 1) Mobile doesn't starts with SIM but starts without SIM? 2) No network? 3) Handset hangs? 4) Phone too slow? 5) Programs not responding? Use *2767*2878#... After giving this code, phone will show this message Custom E2P Reset and then will restart. If not, then switch on your mobile manually .but again remember, this will delete all user data too! So, create a backup before proceeding. Another funny matter, this also resets the user's security code and disables the mobile tracker too! Study Your Samsung Mobile Before proceeding, I must tell you that, all Samsung secret codes starts with *#8999* or *#9998* So, if some code doesn't works then interchange the first digits. *#9999# Shows the current firmware version of the mobile. All master reset codes: *2767*2878# *2767*3855# *2767*7377# and *2767*2070# -------- *8999*0228# or *#228# or *#9998*228# All information about mobile's battery and this also displays the current temperature. Sony Ericsson now, this mobile vendor is too clever! They haven't created any special codes for resetting phones but they only have few codes. To know every thing about your SE mobile, > * <- <- * <- *-> Stands For Right Key <- stands For Left Key Update Service Feature This is a special features provided by maximum mobile vendors. Actually this service offers to upgrade your mobile to its current firmware version or current OS version whatever. The best advantage of this feature is your mobile remains up-to-date with all mobile systems and it also stays up to date in compability with all mobile software, e.g, eBuddy etc. Sony Ercisson Update Service: To start the feature, at first dowbload the Updater FROM HERE. Now if you have installed the program, then start with your phone. Remember, this update service will delete all user data from your mobile! To proceed with update service, in the update Service wizard select your mobile's model number and then remove all SIM and Memory card then connect the mobile to PC with USB, while connecting the mobile, PRESS and HOLD C BUTTON till the updater tell you to release it. Now the updater will check your mobile then it will download the update form its server and then it will install the update. CAUTION: DO NOT DISCONNECT THE PHONE WHILE UPDATING, IF DONE, THEN THIS MAY KILL YOUR MOBILE PERMANENTLY! Nokia Software Updater Download FROM HERE. All the procedures are same as above but you don't need to holding the C or ANY button. Thank You! :crazy: USE ALL CODES AT OWN RISK, THOUGH THEY ALL ARE TESTED!