Eraser Ver.6.06 problem with overwrite of unused disk space


New Member

On 24 JUL 10, I used Eraser, ver.6.06, to run a Task to overwrite the unused disk space on Local Disk (C:\) ( C:\ is a 750GB hard drive in RAID 1 configuration with another 750GB hard drive, WinXP, SP3).
The unused space erasure method was set to: Pseudorandom Data (1 pass). The Randomness data source was RNGCryptoServiceProvider. The box to “Force locked files to be unlocked for erasure” was checked.

Five days before running Eraser, on 19 JUL 10, I ran a Full Backup of C:\ using NovaBACKUP, Ver. 11.1_14. The backup summary showed 227,785 objects and 93.29GB.
On 24 JUL 10, after running Eraser to overwrite the unused disk space, I ran a second Full Backup of C:\ using NovaBACKUP. The second backup summary showed 229,284 objects and 324.98GB.
What happened? The addition of 1,499 objects seems right, but jumping from 93GB to 324GB is hard to understand. Is there a way to get my disk usage back to something under 100GB


Re: Eraser Ver.6.06 problem with overwrite of unused disk sp

Dear Joel,

Thank you for your prompt response. You solved my problem.

For new users seeking a detailed approach, this is what I did. In Windows XP, right click on Start, left click on Explore, go to My Computer, then to Local Disk (C:) and examine the list of folders under Local disk (C:). In my case, I found 23 folders of which 5 folders had long alpha-numeric names (e.g., 88b90193b680d6b59d). Of the 5 folders only one folder was very large (over 200GB) and equal to the "free space" that I had lost. This large folder contained numerous files with random file names consisting of letters numbers and symbols (i.e., ?, $. %, etc.). This is the folder to delete (Just right click on the folder and left click on Delete). The other 4 folders with long alpha-numeric names were very small (ranging in size from 712KB to 1.03MB), contained sub-folders with normal names (i.e., amd64, i386 and update) and their names did not contain any random symbols (i.e., ?, $. %, etc.) only letters and numbers. Do not delete these folders.


Re: Eraser Ver.6.06 problem with overwrite of unused disk sp

Thank you for your useful description. I have included it in my FAQ post on common Eraser problems, as this is an issue which new users do sometimes find difficult.