I have the identical problem and remain convinced that the charging circuit in the MZ-M100 does not work. I purchased a green gumstick battery that says PDA 85NMH which also does not charge in the unit. While still within the warranty period, it had a problem which the repair facility fixed. I have also had 2 HiMD discs fail. How about a class action suit against SONY? Maybe that would get them to deal with the problems with this obviously defective product! Let me know if interested... I know a great lawyer.
