Islam does not forbid women from talking to men, nor men to women if the situation calls and the conversation abides by the boundaries of Islamic sharia. There are many hadiths which confirm the permissibility of men greeting women and women greeting men, as well as the lawfulness of men visiting sick women and vice versa.
However, this does not imply the lifting of all boundaries, so that women start speaking to all men who come and go or that men start speaking to all women, as this is rejected by logic and good taste before being rejected by Islam. It is permissible for a woman to speak to a male relative, a teacher, a neighbor, a supervisor at work, and others according to the requirements and needs of every day life and complex relations amongst people in our days, as long as trust is established, troubles (fitna) are in restraint and conditions are normal.
Indeed, the way in many Islamic countries is for men to greet women and for women to greet men when they meet. They would also exchange conversation (honorable speech) regarding important and relevant matters, with the approval of fathers, husbands and brothers as well as the scholars. We do not deny that some countries accommodated very strict traditions regarding women, so that they become more like prisoners of their own homes until death becomes upon them.
However, even though some scholars may agree with this, it remains that clear, covert and correct legal evidence contradicts these traditions in addition to the objectives of sharia, interests of mankind and the development of age and people.