Most audio formats, including Windows Media Audio (.wma), can be used to generate a MIDI instrumental sequence. It is best to use some dedicated MIDI utilities for this, or alternatively some good audio editing tools, such as WavePad.
Convert Windows Media Audio to MIDI audio.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert wma to mid on Windows
An audio editing software for Windows and Mac
Convert from wma file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.