Failure to index incoming NEW messages in Thunderbird on Linux Ubuntu 7.1]

[Ray Edester]

Beginning on April 1st I found all new messages in Mozilla Thunderbird
to be unreadable and most assume the contents of an old message I can no
longer find in any mail folder.  Going to Edit, Preferences and
Rebuilding the index allows the correct contents.

I generally discount chatter about virus' as pertaining to Windows and
leaving LINUX safe.

However, as this happened on April 1st I'm wondering if my Ubuntu 7.1
and/or Thunderbird has suffered some sort of Malware and trying to
formulate a plan to correct the situation.

Also, I may have received an upddate on April First.

Any thoughts on this subject will be appreciated.

Thank you,

Ray