My sony ericsson k770i does not recognise that my memory card is inserted in the mobile for some reason

so you must go through following solutions.1.try next memory stick in yr phone if not shown it is problem with ur memory house so ,clear your memory house and try again.
2.check your memory stick in another cellphone. if not shown then it is the problem with ur memory stick ,so change your memory stick. so you must go through following solutions.1.try next memory stick in yr phone if not shown it is problem with ur memory house so ,clear your memory house and try again. 2.check your memory stick in another cellphone. if not shown then it is the problem with ur memory stick ,so change your memory stick.