Hi Pako7,
In your other topic (
https://forum.avast.com/index.php?topic=229957.0) you mentioned you have ?Avast? Cleanup installed.
Just wondering if you've run this program before and not allowed it to finish to completion. If you've done that, you shouldn't.
If you did, then the amount of free space would be next to nil on your hard drive. Avast Cleanup needs to write files to the hard drive in the Temporary files folder and will fill up your hard drive as it does so. This is normal behavior.
If Avast Cleanup is not allowed to complete (interrupted by user or cancelled) and thus automatically remove all junk files when finished you will wind up with a mess on your hands and no free space. Guaranteed. Every time.
(Avast should warn all users that using this program has risks and the process of cleaning the hard drive will sometimes take hours
or even days, depending and not to interrupt the cleaning process. They also should say to be prepared to not use your system at all while Cleanup is doing it's thing. Cleaning a 1TB drive of junk files is going to take some time just because it is so large.)
Patience is needed here.
Solution: Move your files off the hard drive to offline as DavidR suggests, else always allow Cleanup to finish.
If running this program on a laptop, run it on AC power until done.
I use Windows Disk Cleanup myself with no issues. Let it finish.
[EDIT:] As for the blinking display, that's the video display driver falling down and restarting. Just worked on a laptop that had the same issue and the fix was to go to the vendor's website and update to the latest video driver. Some laptops have a vendor program built-in that will automatically update drivers and features but you've to run that manually and reboot.
Just don't update the BIOS unless you know what you are doing. You can brick your system if it doesn't work out.