I was trying to find the cause of a problem with altering an Access
mdb file via ASP and ADO. I was told that it was down to NTFS
permissions. I eventually discovered that these permissions are hidden
by an option called "Use Simple File Sharing (Recommended)".

Once unchecked, the "Security" Tab becomes visible under a
file's/folder's Properties. The user IUSR_<machine> can then be added
with Write\Read\Erase permission thus allowing the .LDB (lock file) to
be created, altered and deleted when writes are made to the MDB file.
When the account is added, it's description should be..."Internet
Guest Account <pc domain name>\<machine account name>". The
IUSR_<machine> name will be the something like IUSR_JOE-BLOGGS or
IUSR_DAVIDSPC, you get the idea.

This took me a long time to find out so I hope this posting is useful
to someone.

The setting in question is located as follows (in XP Pro): -

"Start>Control Panel>Folder Options>View>Use Simple File Sharing
(Recommended)", turn this off, it isn't recommended for these
purposes!

David Rocke.