can't delete dirs made on cygdrive from within windows

[Andrew Gingery]

So let’s say I’m at a cygwin bash prompt and I…
cd /cygdrive/c/backup
mkdir test
(I’ve set my umask to be 000)

The dir “test” can not be deleted from windows. All security permissions would indicate that it is delete-able. There are NO handles open to the directory that Process Explorer can find. The dir will delete fine from within cygwin. I have admin rights on the PC. The problem doesn’t happen to files, just directories.

If I do this:
cd ~ (to go to /home/myaccountname)
mkdir test

This “test” directory can  be deleted from windows, no problem.

I’m completely stumped and baffled. I just got the new cygwin dll 1.7.3-1 and this is a fresh “base + rsync only” install on a winXPpro x86 PC.