OT: 'lost' emails

[Voytek]

I suspect this is mail client issue, but looking for any suggestions:

user with Thunderbird says " I'm losing emails, mail is not in inbox, but, when I search, that email shows in search result, but, I can't open the email body" i don't fully understand what he was trying to say, and, won't be able to look at his PC till Monday.

Looking at inbox's 'cur' directory, I can see the'missing' email amongst the other 2000 emails in 'cur'

Is there any indexing I should do on the user's email folder, how?

or, is this purely Thunderbird issue, and, I need to re index Thunderbird?

V
-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.
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