We've been using NSM to delete file stores when the user object is deleted from the tree.

Of the 10'000 accounts that we've deleted today, the file store still remains for 2'000 (ish) of them.

There's no record of any of these users in the NSM logs.
There doesn't appear to be any correlation between the users or the file stores; different containers, different dates of creation, diffeent servers...

The policy isn't complicated, and it's applied to all the correct containers.

We'd staggered the deletion, from initially 10 up to 1000 users at a time, at each stage we noticed that some filestores were missed out. E.g. out of the first 10, 2 weren't deleted.

Any ideas?