Simply seeing a key in your dream means that you will soon have rather unexpected changes in your life. This applies both to the personal and the professional life.
Seeing a very shiny key means that changes in your life will bring about the resolution of a long standing conflict. This is especially true if the dream seemed to be very vivid and peculiar.
Seeing an old, rusty key in your dream signifies that old secret will be told to you or alternatively you will unlock the old secret yourself. A recurring dream of this nature can also signify finding out surprising information about your own past and heritage.
To successfully open a door with key signifies that you need not to worry about not being accepted in your social environment. You will find acceptance even in social environments which you would think would be hostile to you.
Breaking a key while trying to open a door, signifies that in the upcoming time you will have strong feelings of jealousy towards someone. This dream can also signify that you need to be less focused on happenings in the lives of other people.
If you dream that someone gives you a key or keys in your dream it signifies you have found a new way of expressing yourself. If this dream is reoccurring it can indicate that you will have a rather dramatic change in your lifestyle in the next few months and possibly up to a year.
Dreaming that you have lost keys signifies that you will experience some minor, unpleasant events in your real life quite soon.
If in the dream you had found the lost keys it means that you will have success in your family affairs.