We have a very weird issue that just began happening over the past month.
1) ME v6.88 with IMAP has been working fine for years without issue. I realize it's an older version, but none the less it has been flawless,
2) There are no viruses anywhere on our Win2K8R2 server and it is fully patched and updated,
3) In all cases, the user's systems are Clean and Virus free (performed deep scans including root kit),
4) We've crippled AV on the server.
Every once in awhile, I get a user that tells me a message that "was" in their inbox just magically disappeared. The message is not in any Trash or Deleted items folder.
My ME logs show the messages arriving at the server and being deposited/routed to the appropriate SF/inbox. So we know it arrived.
In the case that occurred this morning, the user actually read/opened the email. She did not delete it or move it anywhere.
In one case, the user was looking right at the inbox an a message vanished.
I've had these 3 users use Webmail to eliminate Email Client issues. Two are using Thunderbird, one is using Outlook 365.
One user called me 10 minutes ago and said an email that she saw in here inbox is now gone - she is using Webmail.
We've ran the ME Diags, checked every Tab file, checked the server disk for corruption, deep virus scans - you name it we've done it.
We cannot physically reproduce this anomaly - it just randomly happens.
Does anyone have any ideas as to what is causing this?