my outrunner motor get stopped when i throttle to mid position. please suggest me the cause of this problem.

Re program your ESC...
Where are you in Lucknow?

Sir, is there any other method of reprogramming the ESC other then soldering.

Firstly, no sir.
Secondly, there is similarity between programming/reprogramming and soldering ESC. BTW, what are you soldering in it other than female bullet connectors. Which ESC is this...

 i am connecting programmer to ESC by soldering. i am using FMT 30 amp ESC.

@prateek where do you live i or utkarsh can help you..
it seems you are new to this hobby and they are many things which you should be aware of as some wrong doing can lead to disaster(just hyping things ) so let us guide so that u don't do somethings that we have done before

Regards
yash

please  suggest me ways to calliberate the ESC.

Although the beep pattern differs from ESC to ESC but the setup and procedure remains same usually.
The procedure for calibration is as follows:
1.) Disconnect the battery and all previous setup.
2.) Install your receiver and connect the ESC wire to the channel 3(Throttle) of your receiver.
3.) Now switch on your radio and increase the throttle to maximum.
4.) Now connect the battery.
5.) You'll hear beep pattern. Although it is somewhat different in different ESC's but on the second beep you need to bring throttle to zero.      Disconnect the battery and connect it again(Keep throttle zero after disconnecting the battery)
Now your ESC is calibrated.
I hope after this your problem would get solved.

i think problem lie in my transmitter. speed of motor continuously increases with out even throttling and then suddenly it get stooped. i am using simonk 30 amp ESC and turnigy tx and rx .