fixing c stage 2

Open | Software. 86 season 2 My computer was acting up a bit and decided to restart it and then this popped up on my screen Fixing (C:) Stage 2: 89% (986242 of 1040274) Total: 78%; ETA: 0:01:18 Anyone know why this popped up and if it’s something to worry about? Is this an update or a fix on the hard drive? Why is the ETA getting longer? Thanks in Advance!