PPTX coder not found

[twells]

When trying to create a thumbnail of a PowerPoint file (PPTX), I am getting an error that the coder can not be found. Does this coder exist?

Example:

magick 57-source.pptx 57.png
magick: unable to open module file 'C:\Program Files\ImageMagick-7.0.8-Q16\modules\coders\IM_MOD_RL_PPTX_.dll': No such file or directory @ warning/module.c/GetMagickModulePath/675.
magick: no decode delegate for this image format `PPTX' @ error/constitute.c/ReadImage/556.

Thanks for the help.

[snibgo]

"magick -list format" will list the formats available. PPTX isn't listed.