nconvert syntax: .ico to .bmp?

[Guidance]

I'm trying convert windows icon or bmp file to jpg as below:

D:\tmp>"d:\program files\xnview\nconvert" -quiet -o d:\tmp\test.jpg -out jpeg d:\tmp\music.ico

but got this response:

Error: This picture cannot be written using this format (d:\tmp\music.ico)

Where's wrong?
BTW, does nconvert support quotes if the path contains spaces? Thanks!

[xnview]

I'm trying convert windows icon or bmp file to jpg as below:
D:\tmp>"d:\program files\xnview\nconvert" -quiet -o d:\tmp\test.jpg -out jpeg d:\tmp\music.ico
but got this response:
Error: This picture cannot be written using this format (d:\tmp\music.ico)
Where's wrong?

JPEG can't be in colors, you must convert it. Use -truecolors

BTW, does nconvert support quotes if the path contains spaces?

Yes, use " ("my folder"
Pierre