Emails went missing (windows mail/vista)

[dumbfounded]

Quite often this happens, I get an email in my inbox, read it then when I
came back to have another look, its gone.

I dont know what happens, I didnt delete nor move it but it just
disappeared. Anyone can help? Is it the setting in my computer?

 

[mac]

Quite often this happens, I get an email in my inbox, read it then when I
came back to have another look, its gone.

I dont know what happens, I didnt delete nor move it but it just
disappeared. Anyone can help? Is it the setting in my computer?

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