No autochk has ever been scheduled ,but the message came up that it was.I'm also typeing the chkntfs c correctly and placeing a space before the c .I went back and did this again with the space and a small black screen came up then blinked off.I also went to my computer,right clicked on c ,properties,tools,clicked on option to check volume for errors and message said Windows unable to complete the disk check.To the best of my ability , I'm telling you that my computer want check drive C.I've also read the the list on how to fix Windows built in defragmenter.