Microsoft Image Exchange File
Microsoft Picture it and Microsoft PhotoDraw are two programs that can be used for creating and editing graphic images.
Both programs support the use of layers and are both able to edit these layers.
When saving files that use multiple layer the file extension .mix is used.
Both these programs have since been discontinued.
» Microsoft Photodraw 2000
How to open .mix files?
Software to open .mix files
What are .mix files