Your reference to "mysterious" shadowing by Vista, is nothing more than a workstation level implementation of Volume Shadow copy which has been around since Server 2003.
If you goto Control Panel | System Properties | System Protection Tab, you can easilly turn on or off shadow copy behavior by drive -
including external drives.
From the built in Help Documentation found from this Dialog:
[span style=\'font-size:8pt;line-height:100%\'] How are shadow copies created?
Shadow copies are automatically saved as part of a restore point in System Properties. If System Protection is turned on, Windows automatically creates shadow copies of files that have been modified since the last restore point was made. Typically restore points are made once a day. If your hard disk is partitioned or if you have more than one hard disk on your computer, you need to turn on System Protection on the other partitions or hard disks.
Note
Only one version of a file is saved as a shadow copy. For example, if you modify a file several times in one day,
only the version that was current when the restore point was made is saved. (my emphasis)
How do I access previous versions of a file and folder?
Right-click the file or folder, and then click Restore previous versions.
You'll see a list of available previous versions of the file or folder. The list will include files saved on a backup as well as shadow copies, if both types are available. [/span]
Please note that "Shadow Copies" are *never* restored without specific user intervention. Possibly you are confusing this with the Windows DLL cache? .8bi files are not considered system libraries by windows, and in no instance wopuld ever be affected or overwritten by the DLL cache.
You might consider downloading Mark Russinovitch's excellent Process Explorer:
http://technet.microsoft.com/en-us/sysinte...s/bb896653.aspx A great tool for determining which files, dll's etc are opened by a particular process . . .
hth - John