SE K750i displaying 'insert sim' even though sim is inside.

do a master reset from the meniu of the phone

your internal aerial is damaged

This is because Operating System (OS) of your mobile has been corrupted. U can't do anything to fix this by yourself. U can get it repaired only by contacting nearby SE authorised service centre. [Even i had a same experience in my SE W810i]

my mobile name is sony ericssion k750i it's do not work joy stick properly since 1 month pl solve this

My SE K750i handset has been fallen down from a height of 6ft. It got switched off. and was working well when I started except the camera. even after opening the shutter its not displaying the camera its only showing the wallpaper. Not even from camera menu. So I can't take any snap or video. Please help me as what to do . some times when i am going to the menu it is hanging.authorised dealer told that it has virus.please help to solve this problem

do all the contact pins on the phone reach the simcard?
you can try to pull them up a little bit carefully.

keep ur phon on the reilwey track

i had the same problem - you will need to flash your phone with the newer firmware. is your M2 a 2gig? mine was.

After i flashed it , it worked great - you can use wotan server or contact me as we flash those all day long - horizonwirelessonline.com

thanks

well... seem like you phone has got locked from the network may be accidently in case of stolen better check you service provider and if they say every thing is fine try to flash your mobile .it has some perticular number to flash it try these number *#7780# (password 12345)

Flash it, change erom