Hi Kelly
You have not other option but to run check disk on that drive, when the power was removed form your PC, that caused a disk error and that needs to be repaired.
Check Disk will not harm your PC in any way, it is safe to run . . .
Press the Shift Key and click Restart
Your PC will boot into the Windows Recovery Environment
Go to Troubleshoot - Advanced Options - Command Prompt
Run this command and hit Enter:
chkdsk C: /f
Wait for that to complete and run this command:
chkdsk C: /r
That command will take time to complete, then restart your PC
Please make sure the power does not disconnect when those commands are running . ..