hi Dominik.

To the users, it will appear as if the attachment is delivered directly to
their account. ie. the attachment will count against their mailbox size/size
limits, will be downloaded if using an OST/cached mode, etc. But within the
store itself, the attachment will be created once, with pointers from each
mailbox to the single attachment.

One exception to this is when you have multiple recipients that are spread
across multiple stores. If you have 5 recipients in storeA and 5 in storeB,
an attachment will be created in each store.

Another is when a recipient modifies the attachment in any way. When that
happens, a copy of the attachment is made and the user gets his/her own
copy, and drops the pointer to the original attachment.

And using something like exmerge to export data to PST and back into the
store will break SIS and will create a copy for each mailbox as the data is
reimported from the PST.

But, to the user, this is all transparent.

David.