HTC mail app resetting folder view to all mail

[Android Central Question]

Hi, hope somebody can help. Small, but irritating pb. Using HTC Mail app to view access multiple mail boxes which works fine. However, regularly (at least once per day) instead of viewing the Inbox (only, which I selected), it resets to viewing all folders. Does the same for all three mail boxes I use (Gmail, Hotmail, NTL/Virgin).
Thanks
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