This is not totally free, but the trial is full & not time limited.
It's simple, works great, Just be sure to set the options before using it.
I turned off the "delete cookies", otherwise you got to remember all your logins @ forums like this one and enter them again.
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Disk CleanUp 2000 is a small disk utility designed to clear previously deleted files. Deleting a file will normally just remove the file's directory entry, but the data itself still remains on the disk. CleanUp will completely eliminate the contents of your deleted files.
Disk CleanUp provides options to specify an NSA approved disk erasure method and background execution priority. Disk CleanUp works with any FAT16 or FAT32 hard drive, as well as Microsoft Windows NTFS volumes.
Disk CleanUp 2000 can also be configured to optionally erase temporary files from web browser and user-defined folders.
Disk CleanUp 2000 now includes DiskWipe, a small console utility that performs the same functions as Disk CleanUp, but can be used with MS DOS or in a batch command file.
Disk CleanUp 2000 can be configured to optionally place its program icon in the taskbar notification tray.
Click on the following link to view a screen shot of Disk CleanUp
as for "multipass" , yes it will do it, and you have your choice of about 15 major security wipe styles.
However I tested it with the simple "write zeros' one time pass.
and then tried to find anything on the deleted space. I tried GetDataBack & also several forensic appz such as EnCase.
All reported nothing but ZEROs, they could find nothing.
If you have such security needs for multipass so you can remove residual magnatism, then your security needs are far beyond "freeware". ..and I wish you the best of luck at whatever you're doing.
Anyway, you can wipe your empty space all you like, but what about the files still on your system ?