Black Candles are bearish lines in candlestick and candlevolume charts. They signify that the closing is lower than opening for that time period.
CHKDSK, short for Check Disk, is a utility that checks the integrity of the files and file structure of your hard disk. I'll walk you through it. I have disk problems and you said I should run CHKDSK. Great.
To begin the scan, right-click on the Drive which you wish to check and select Properties. Next, click on Tools tab and under Error-checking, click on the Check button. This option will check the drive for file system errors. If the system detects that there are errors, you will be asked to check the disk.