I have a 8700 with a 2 TB HDD and a SSD running windows 10 and this week I started receiving a low disk space error. When I inspected my drives under my computer my OS indicate I have 1.8 TB of free space and there is a second drive listed as Local Disk(I:) which is almost full show a  size of only 450 MB or so (not exact). When I click on this drive it appears empty even when I have selected hidden folders to show and when I check my storage in windows 10 it indicates all new data is being written to my C: drive. I also reviewed the storage/ disk management in the my computer sub menus but I don't even show that "I:" drive listed as a partition.

Can anyone tell me what this "I:" drive is used for and why I cant I clear up whatever if filling it or see any folders or data in it? The low disk space warning its creating is not affecting my system performance that I can yet tell but I like to address it before it becomes an issue.