All i want to know is how to fix this. I'm hoping there is a patch, etc that is out there now or soon that somebody can say.
Select one of the Drives and Get Info in Finder. Look at the top of the info window and see what it says under Format.
If it is NTFS the reason you can't write is because OS X has never had the capability to write to a Windows hard drive.
When you bought the drive, the manufacturer formatted it for Windows and gave you some software to install to make it writable. Unfortunately, you installed that software and it no longer works because the manufacturer didn't update it for El Capitan.
You can either format the drives with the native OS X file system which will require that you move your data, then restore it after formatting, or you contact the manufacturer and get an update to the software which you will likely have to update at every OS update or upgrade.
If it is formatted Mac OS Extended, then what does it show in the Sharing section of Get Info.