Boot camp partition disappeared after El Capitan installation, How do i fix?

After installing El Capitan when i went to boot into windows 8 via bootcamp disk it was not an option the disk had simply disappeared when i go into "diskutil list" in terminal it shows the partition as ( 4: Microsoft Basic Data 100.0 GB disk0s4 ) but will not come up as a drive. I am also unable to repartition and delete the drive in bootcamp as it claims error. i am unsure what to do at this point i hope someone can help!