I will not answer your question directly. I'll give you the GOOGLE on it:
http://www.google.com/search?&q=ALL+OPENED+HANDLES+TO+THIS+VOLUME+WOULD+THEN+BE+INVALID
The second article is from Microsoft and explains it.
Bob
I try to convert my system to NTFS, during the process I get this messages:
'The type of the file system is FAT32.
Enter current volume label for drive C:
Convert cannot run because the volume is in use by another
process. Convert may run if this volume is dismounted first.
ALL OPENED HANDLES TO THIS VOLUME WOULD THEN BE INVALID.
Would you like to force a dismount on this volume? (Y/N) y
Convert failed to dismount the volume.
Convert cannot gain exclusive access to the C: drive,
so it cannot convert it now. Would you like to
schedule it to be converted the next time the
system restarts (Y/N)?'
The question is what it mean by 'ALL OPENED HANDLES TO THIS VOLUME WOULD THEN BE INVALID.' ??
Should I choose Y (Yes)?
Thank You

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