This is the results from the CHKDSK. The computer was shut down, and restarted, but it seems to have done the job.
How do you initiate the verification?
Checking file system on C:
The type of the file system is NTFS.
A disk check has been scheduled.
Windows will now check the disk.
Stage 1: Examining basic file system structure ...
473600 file records processed. File verification completed.
15983 large file records processed. 0 bad file records processed.
Stage 2: Examining file name linkage ...
563254 index entries processed. Index verification completed.
0 unindexed files scanned. 0 unindexed files recovered to lost and found.
Stage 3: Examining security descriptors ...
Cleaning up 16706 unused index entries from index $SII of file 0x9.
Cleaning up 16706 unused index entries from index $SDH of file 0x9.
Cleaning up 16706 unused security descriptors.
CHKDSK is compacting the security descriptor stream
Security descriptor verification completed.
44828 data files processed. CHKDSK is verifying Usn Journal...
41417408 USN bytes processed. Usn Journal verification completed.
Correcting errors in the master file table's (MFT) BITMAP attribute.
Correcting errors in the Volume Bitmap.
Windows has made corrections to the file system.
No further action is required.
487821311 KB total disk space.
148533680 KB in 281569 files.
206000 KB in 44831 indexes.
0 KB in bad sectors.
598739 KB in use by the system.
65536 KB occupied by the log file.
338482892 KB available on disk.
4096 bytes in each allocation unit.
121955327 total allocation units on disk.
84620723 allocation units available on disk.
00 3a 07 00 05 fa 04 00 7e 01 09 00 00 00 00 00 .:......~.......
2f bf 00 00 28 7e 00 00 00 00 00 00 00 00 00 00 /...(~..........
Windows has finished checking your disk.
Please wait while your computer restarts.