We seem to have had some kind of problem last night where a bunch of users (myself included) are having the missing blob issue where theres still metadata but no file on disk.
There are some pretty good discussions about this with scripts such as
[SOLVED] Missing BLOB errors from zimbra-4.5.10
Ajcody-Notes-No-Such-Blob - Zimbra :: Wiki
but a lot of these contain scripts which are only for 4.x.
Right now because I know the problem seemed to happen last night, i'm restoring the user's account from yesterday at a known good time. i'm running zmblobchk on the account to find which ones are missing. then i'm manually copying hte .msg files from the restored account to the existing one and it's fixing it.
is there a better way?