while deleting files, the system launches pop ups stating that the file can
not be found and whether i would like to create it.  
Haven't seen this listed anywhere, but I have had several occurances when I
would delete a directory, or group of files. If I can take a guess at what is
happening, I would say that when the uac file deletion approval screen pops
up, the files are actually already being deleted. so that when the program
actually catches back up again, due to lag, some are no longer present. When
I deleted my windows.old directory, (pre installed xp just to run thru an
update scenario) I had to skip file creation almost 15 times. I have the
vista beta diskeeper pro 10 loaded and run defrag as needed. Does seem to
make a big difference in how vista runs, tho I do not know if this has any
bearing on the problem. Have included this in bug reports to both microsoft
and diskeeper.